Forty Indian construction workers have been kidnapped in the northern Iraqi city of Mosul, which was overrun by insurgents last week, the Indian government said Wednesday.

Syed Akbaruddin, a spokesman for India’s External Affairs Ministry, said at a news briefing that the workers, who hail largely from the state of Punjab, were abducted. He said the government was still investigating the circumstances of their capture, which was confirmed through various sources, including humanitarian groups such as the International Red Crescent. Authorities had not yet received any ransom calls from the captors, he said.

“This has triggered for us a very difficult situation,” Akbaruddin said, adding that the country was working with authorities in Iraq to resolve the situation. The country’s embassy in Iraq will remain open, and a special envoy, Suresh Reddy, a former ambassador to Iraq, has been sent to help mitigate the crisis.

The Times of India first reported the kidnappings in Wednesday’s editions, writing that the employees had been working on projects in Mosul and were trying to leave the battle-ravaged area when they were “waylaid” by militants suspected to be from the Islamic State of Iraq and Syria. The Sunni militants seized control of the largest city in northern Iraq on June 10.

Akbaruddin said that the missing workers were employees of Tariq Noor al-Huda, a Baghdad-based construction firm. According to its Web site, the company had previously done mosque reconstruction projects in Karbala, a holy city for Shiite Muslims. The Web site said the company had a contract to build a condominium complex of 1,000 units with a mosque and sports stadium in Mosul. A woman who answered the phone there Wednesday confirmed that the construction company was part of a larger trading and construction conglomerate and said the firm was working with the authorities to help free its employees.

Akbaruddin said about 10,000 Indian nationals have been working in Iraq, including about 100 in the areas affected by the recent violence. Forty-six Indian nurses are trapped at a teaching hospital in Tikrit, the home town of former Iraqi leader Saddam Hussein about 110 miles northwest of Baghdad.

One of the nurses, Marina Jose, who is from the southern Indian state of Kerala, called for their rescue in a telephone interview Wednesday. She said the hospital was nearly deserted because most of the staff had fled. She was hunkered down with other nurses in their hostel quarters awaiting evacuation. The nurses hear occasional gunfire and explosions but so far have been insulated from the violence, she said.

Red Crescent workers were able to check on them, and those who want to leave will be evacuated, although road routes remain unsafe, the government said.

"We are worried about the safety, particularly after the kidnapping of Indians,” Jose said. “We request the government to take necessary steps to evacuate us. We are going through a tough time and hope things will settle down soon.”

Jalees Andrabi contributed to this report.