An American teacher Debra Lobo was shot and wounded in the southern Pakistani city of Karachi by men claiming to be Islamic militants. (Reuters)

An American teacher was critically wounded Thursday in Karachi after being shot in the head in an apparent terrorist attack that raised the possibility of links to the Islamic State, police said.

Authorities said Debra Lobo was vice principal of Jinnah Medical and Dental College, a private medical college in the southern city. Police said Lobo, 55, was shot twice when two men on a motorcycle began firing into her car.

“The initial investigation suggest that this was a pre-planned terrorist attack and was made over the lady because of her national identity,” said Asif Farooqui, a Karachi police official. The two attackers escaped, he said.

Lobo’s father, James Kachic, said his daughter grew up in the San Fernando Valley in California but moved to Pakistan about 30 years ago to work as a Christian missionary. Lobo was married to a Pakistani man and was rearing two teenage daughters in Karachi, Kachic said.

“We have been involved with our church for quite a while, forever, actually, and she grew up that way,” Kachic said in a telephone interview from California. “When she went to UCLA, she was president of the Christian fellowship, and, over the years, the Lord put it in her heart that she wanted to be a missionary in the subcontinent, which happened to be in Pakistan.”

Pakistani police officers examine a car of a U.S. citizen Debra Lobo, targeted by gunmen in Karachi, Pakistan, Thursday, April 16, 2015. (Fareed Khan/AP)

The U.S. Embassy in Islamabad had no immediate statement on the attack. At a news briefing Thursday, U.S. State Department spokesperson Marie Harf said: “We have seen the reports that a U.S. citizen was injured in a shooting incident in Karachi. Our consulate general . . . there is in close contact with Pakistani authorities and is working to obtain more information. The local police authorities in Pakistan are handling the investigation.

Nawab Baqar, an administrator at the Jinnah college, said Lobo began working at the institution as a teacher around 1996. Her father said she had been trained as a physician’s assistant and used her medical background to try to improve Pakistan’s health-care system.

“She was very intelligent, very friendly, and everyone is very sad over what happened to her,” said Baqar, adding that he knew of no previous threats against Lobo.

A Karachi police official, who spoke on the condition of anonymity because he was not authorized to speak to the media, said the gunmen left a note on the victim’s car implying affiliation with the Islamic State.

The note said the attack was revenge for a police operation in Karachi last week that killed five suspected terrorists, including the head of the local wing of al-Qaeda, the official said.

Agence France-Presse said the note threatened more “ambush” attacks on Americans.

In recent months, Pakistani military and intelligence officials say they have detected only scattered signs that Islamic State militants posed a rising threat in Pakistan, which is home to a host of groups including the Taliban. But some militants with past affiliation with al-Qaeda or the Pakistan Taliban have announced that they are now also operating under the banner of the Islamic State, also known by the abbreviations ISIL and ISIS.

Karachi residents have also been concerned by what they say is an increase in pro-Islamic State graffiti in some neighborhoods.

Abdul Waseem, a lawmaker from Karachi affiliated with the secular Muttahida Qaumi Movement (MQM), said the shooting should be an “eye-opener” for Pakistanis.

“MQM has been pointing toward this threat from ISIS and its [graffiti] in Karachi for months, but no one listened,” said Waseem, whose party has also been targeted by security officials in recent months over allegations it maintains an armed wing in Karachi. “Now, will the government wake up to this threat or only when it starts bombings like the Taliban?”

Despite a decade of violence, attacks on foreigners in Pakistan remain relatively rare, although a Pakistani American doctor from Columbus, Ohio, was fatally shot last May near Lahore in another targeted attack.

Karachi, a metropolis of about 22 million people, is one of Pakistan’s most volatile and dangerous cities.

Over the past 18 months, Pakistani paramilitary officers have been engaged in a major operation against Islamist militants and criminal gangs in the city.

But some parts of Karachi remain a refuge for the Pakistani Taliban and al-Qaeda militants.

As the brutality of Islamic State militants in Iraq and Syria surfaced last year, Kachic said his family had grown increasingly concerned about Lobo’s safety in Pakistan. But he said Lobo never “raised any concerns.”

“Then again, we are her parents. She probably didn’t want to worry us,” Kachic added. “As parents, we knew it wasn’t the best place for her to be, but that is where her heart told her to be, so we released her to the Lord and had Him take care of her.”

Aamir Iqbal in Peshawar and Nisar Mehdi in Karachi, Shaiq Hussain in Islamabad and Julie Tate and Carol Morello in Washington contributed to this report.

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