KABUL, Afghanistan — Demonstrators in Afghanistan attacked police officers along a road leading to the U.S. Embassy in Kabul as tensions remained high Monday in the Muslim world over a movie trailer that mocks the Prophet Mohammed.

U.S. embassies and consulates were on alert for further backlash over the anti-Islam video, which was produced privately in the United States.

At least 15 policemen were injured and two police vehicles burned when the protest of about 300 Afghans at an outer security perimeter several miles from the embassy turned into a melee, a senior Afghan police official said on condition of anonymity because of the sensitivity of the situation.

Protesters also clashed with police in Indonesia and in Pakistan.

The violence is the latest fallout from a low-budget, amateurish 14-minute movie trailer posted on YouTube that mocks the Prophet Mohammed as a womanizer, child molester and killer. Islam forbids any depictions of Mohammed, and blasphemy is taboo among many in the Muslim world.

Monday’s incidents come six days after protests erupted in Egypt and Libya, and spread to more than 20 nations with sometimes violent results.

The attack on the U.S. Consulate in Benghazi, Libya, left Ambassador Chris Stevens and three other Americans dead.

The leader of Lebanon’s Hezbollah movement, meanwhile, called for renewed protests Monday over the trailer.

Speaking Sunday on Hezbollah’s al-Manar television service, Hassan Nasrallah said the trailer, which has been posted online, “represents a dangerous turn in the war against Islam and the great prophet, peace be upon him.”

“The people who should be accountable, and brought to justice as well as punished and boycotted, are those directly responsible for the film and those who support them and protect them,” Nasrallah said. “And it is the United States of America that is at the forefront of those.”

U.S. President Barack Obama has disavowed the trailer, saying the United States rejects “the denigration of any religion, including Islam.” He also said, “There is no excuse for attacks on our embassies and consulates.”

Not all of the protests have been violent, and the protesters represent only a small fraction of populations.

In Pakistan, about 1,200 protesters Sunday clashed with police armed with batons and a water cannon near the U.S. Embassy in Karachi, a city of about 13 million people. One protester was killed and 45 police officers injured, officials said.

In other developments:

Security measures tightened

While U.S. Secretary of Defense Leon Panetta told reporters over the weekend that the worst of the violence appeared to be over, the United States was taking further security measures anyway.

Nonessential personnel have been ordered to leave the American diplomatic missions in Sudan, Tunisia and Libya. In Yemen, consular services have been suspended until the end of the month following a violent protest last week.

On Monday, German, Canadian and British consular services in Khartoum, Sudan, remained closed after protesters attacked a compound housing the German and British consulates in the city.

But there were signs that some diplomatic missions that had been targeted by protests were trying to get back to business.

At the U.S. Embassy in Cairo, the scene of five consecutive days of protests, the mission returned to full staffing Sunday, the U.S. State Department said.

Calls for tolerance

Despite U.S. government officials’ condemnation of the movie trailer for “Innocence of Muslims,” some in the Muslim world do not accept that the movie could have been produced without Washington’s approval, Council of Foreign Relations scholar Ed Husain said.

That is particularly true for people raised in countries whose governments must authorize any film production, he said.

The movie trailer was privately produced by a man whom federal officials identified as Nakoula Basseley Nakoula, a California man on probation for bank fraud.

Over the weekend, federal probation authorities questioned Nakoula to determine whether he violated his parole.

Reports that Nakoula, who initially told The Wall Street Journal he was an Israeli, is a Coptic Christian have raised concerns about a possible backlash against the minority religious group in Egypt, where tensions between Copts and Muslims have risen in recent years.

Muslim and Coptic leaders were scheduled to hold a joint news conference Monday in Los Angeles to condemn the violence.

Targeting a press club in Pakistan

At least one person was killed Monday when protesters clashed with police in an anti-American demonstration in northwest Pakistan’s tribal region along the Afghan border.

About 100 people took to the streets in a demonstration organized by university students in the Lower Dir district of the Khyber Pakhtunkhwa province, police official Ehsanullah Ullah said.

The death occurred when police fired warning shots into the air to disperse protesters who were storming a local press club, he said. Authorities were investigating whether the death resulted from a police bullet.

In Indonesia, protesters threw rocks and used slingshots to launch marbles at riot police outside the U.S. Embassy in Jakarta on Monday. Police responded with tear gas.

Blocking access to the movie trailer

Google India has blocked access to the movie trailer, India’s external affairs spokesman Syed Akbaruddin said Sunday in a statement.

“In connection with recent events, we would like to reiterate that India has always strongly condemned all acts that disparage religious beliefs and hurt religious sentiments,” Akbaruddin said.

“The Ministry of External Affairs is in touch with U.S. officials who share our concerns on the matter. Google India has, in compliance with Indian law, blocked access to the offensive material.”

The move by Google India follows news last week that YouTube had restricted access to the video.

The Afghan government has ordered an indefinite block of YouTube to prevent people there from watching the clip.

More arrests in consulate attack in Libya

Libyan authorities made more arrests in connection with the attack on the consulate that killed Stevens and the three other Americans.

Mohamed al-Magariaf, the head of Libya’s General National Congress, said Sunday that about 50 people had been arrested, though another senior government official said the number was lower.

The official said that as many as 50 people had been questioned but not all were detained. All of them had attended a protest outside the consulate, but they had not all necessarily taken part in the violence, he said.

The latest arrests were in addition to four that Libyan authorities made Thursday.

U.S. officials have said they believe extremists carried out the attack on the consulate in Benghazi, but did so after a spontaneous protest began outside the building, said Susan Rice, the U.S. ambassador to the United Nations.

FBI agents were interviewing witnesses outside Libya but had not entered the country, federal law enforcement officials said.

— CNN’s Nasir Habib, Reza Sayah, Jessica King, Chelsea J. Carter, Tom Watkins and Greg Botelho contributed to this report.