Pakistan will pursue murder charges against a U.S. consular employee suspected of shooting two armed men during a possible robbery attempt, a prosecutor said Friday as protesters called for the American to be severely punished.

The killings in this bustling city on Thursday have attracted intense media coverage in Pakistan, and the government — already viewed by some critics as being subservient to the United States — will be under pressure to allow the law to run its course.

Many Pakistanis already regard the U.S. with suspicion or enmity because of its occupation of neighboring Afghanistan and regular missile attacks against militant targets in Pakistan's northwest. Islamist and rightwing opponents of Washington and the U.S.-allied government here said the incident was a further example of American brutality.

In a sign of the political sensitivities surrounding the case, Interior Minister Rehman Malik was asked by a lawmaker in parliament whether he was trying to set the American free. "I will never abet a criminal," replied Malik.

A third Pakistani was killed following the shootings when he was hit by a U.S. vehicle rushing to aid the American, who was also in a car, according to police. Officers have said the driver of that could also face charges.

Police officer Umar Saeed said the American, who has not been named by U.S. authorities, had told officers he had withdrawn money from an ATM shortly before the incident and was acting in self-defense. Other Pakistani officers have said the men were likely robbers, were on a motorbike and both were carrying pistols.

Rana Bakhtiar, deputy prosecutor general for Punjab, said the state would pursue murder charges.

"He has killed two men. A case is registered against him on murder charges," he said.

Bakhtiar spoke after the American appeared in a Lahore court where judges ordered him to remain in police custody for six days. Police will now investigate the case before filing it with the court, which will then charge him.

The man has been named by Pakistani officials but the U.S. State Department says the name is incorrect.

Although the U.S. Embassy has not said what position the man held at the consulate in Lahore, why he was armed or whether he qualifies for diplomatic immunity, the U.S. is claiming that the man holds immunity.

U.S. officials who spoke on condition of anonymity because the legal case is pending said the U.S. has asserted the man's immunity in discussions with Pakistan and sought access to the man by U.S. Embassy personnel. The U.S. is trying to free the man quickly, officials said.

Western diplomats travel with armed guards in many parts of Pakistan because of the risk of militant attack. Lahore has seen frequent terrorist bombings and shootings over the last two years, though the city's small expatriate population has not been directly targeted.

In a two-sentence statement, the U.S. Embassy confirmed that a consulate staffer "was involved in an incident yesterday that regrettably resulted in the loss of life." The U.S. was working with Pakistanis to "determine the facts and work toward a resolution," it said.

In the capital, Islamabad, and the city of Karachi, several dozen people burned U.S. flags and chanted slogans.

"Hang the U.S. spy, the killer of three Pakistanis," read one placard.

The issue of American diplomats or their security details carrying weapons inside Pakistan was a hot-button subject last year among certain politicians and sections of the media purportedly worried about the country's sovereignty. They were frequently presented as a threat to ordinary Pakistanis.

"The Americans feel they can kill any Pakistani that they want, because the blood of Pakistanis is cheap for the Americans," said Shireen Mazari, a prominent rightwing commentator.

Despite the sensitivities of the case, it seems unlikely either country will allow it to seriously affect ties because the relationship is vital for both. Washington needs Pakistan's support to stabilize Afghanistan and defeat al-Qaida, while Islamabad relies heavily on U.S. aid and diplomatic support.

Robbers on motorbikes pulling up alongside cars and holding them up is a common crime in Pakistani cities.

Americans and other foreigners have also been frequently targeted by Islamist militants in Pakistan.

In the northwestern city of Peshawar in 2008, gunmen shot and killed a U.S. aid worker as he drove to work. Suspected militants also opened fire on the vehicle of the top American diplomat in the city the same year, but she survived the attack.