Kabul, Afghanistan - Afghan police opened fire on a mob trying to storm a NATO peacekeeping base housing Norwegian troops on Tuesday, killing four people and wounding 18 as protests over cartoons depicting Islam's Prophet Mohammad flared again.
British troops were being sent to the northwestern city of Maymana to secure the airfield after crowds attacked a NATO base with guns and grenades.
"Police had to open fire. Some people are aiming to disrupt and disturb security," said Azim Hakimi, spokesman for the provincial security department.
"Some people used guns," he said.
Crowds of young men also threw grenades and petrol bombs at the camp manned by Norwegian troops. Two Norwegian soldiers were slightly hurt.
A Dutch peacekeeper was hurt by a stone during a protest in Baghlan, also in the north, the provincial governor said.
The Norwegians fired teargas while NATO F-16 jets flew over Maymana in a show of force, a spokeswoman for the NATO-led International Security Assistance Force said.
"ISAF is operating under difficult circumstances and is exercising the fullest possible restraint. Reinforcements have been sent," a NATO official in Europe said.
"The situation is still out of control, but we have established some kind of a show of force with F-16s," Norway's defense ministry said.
An ISAF spokesman declined to say how many British troops were being set to secure the airfield.
The United Nations said non-essential staff were being evacuated from the city. U.N. and aid groups offices were attacked during bloody riots in May sparked by a Newsweek magazine report about desecration of the Koran.
There were also protests in Jalalabad in the east, Herat in the west and the capital, Kabul, where for a second day crowds of young men stoned the Danish embassy before club-wielding police beat them off. Windows of nearby houses were smashed.
At least three Afghans were killed in protests in different parts of the country on Monday.
"ISLAM IS DEFAMED"
Across the border in Pakistan, about 5,000 Islamists paraded through Peshawar, the capital of North West Frontier Province, which is ruled by an Islamist coalition made up of several pro-Taliban groups.
Another 5,000 people rallied in North Waziristan, a restive tribal region that has been the scene of battles between Pakistani security forces and al Qaeda-linked militants in recent years.
The protests in Pakistan's North West Frontier Province were the largest since the beginning of the controversy.
"Islam is being defamed through such cartoons. It is a terrorist act," said provincial chief minister Akram Durrani, who led the rally. "Those responsible for publishing such cartoons must be punished under international law."
The controversy over the cartoons was reignited when several European newspapers reprinted the caricatures, including one showing Mohammad wearing a bomb-shaped turban, saying press freedom was more important than religious taboos.
The Islamists in Pakistan directed their anger against the United States even though the cartoons have hardly been published in the U.S. media and the United States criticized their publication.
"We are condemning America because it is patronizing those who printed the cartoons," said cleric Mohammad Sadiq.
Pakistan, a key ally in the U.S.-led war on terrorism, summoned diplomats of several European countries last week to lodge a protest over the reprinting of the cartoons.
While the street protests have failed to draw big crowds in Pakistan the issue has offended many of the Islamic nation's population of 150 million.
"What has been published is absolutely wrong, but it is up to the central government to lodge a protest," said Mohammad Aqeel, a shopkeeper, who did not take part in the demonstration.
His views were echoed by Pakistan International Airlines pilot Captain Kashan Dodhy and former TV presenter Ayesha Khan.
"Obviously this is something extremely wrong, and to protest against it is our right," Dodhy said. "But that doesn't mean people should resort to violence -- Islam is a peace-loving religion.