Dozens of people have died as an overloaded ferry sunk in the Tigris near Mosul in Iraq, according to local officials.

Most of the casualties on the ferry were women and children who could not swim, said the head of Mosul’s Civil Defence Authority, Husam Khalil.

He said the ferry had been loaded to several times its capacity. “It can normally carry 50 people. There were 250 on board before the incident,” he said.

Five ferry workers were arrested after late on Thursday, security sources said. Rescue workers were still looking for missing passengers.

The boat was ferrying people to a man-made island used as a recreational area by families, according to one witness.

“I was standing near the river bank when suddenly the ferry started to tilt left and right, and passengers began screaming before it capsized,” said Mohamed Masoud, a local civil servant.

“I saw women and children waving with their hands begging for help but no one was there to rescue them. I don’t know how to swim. I couldn’t help. I feel guilty. I watched people drown.”

Medical officials said the death toll was at least 79. Health ministry spokesperson Seif al-Badr said the dead included 33 women, 12 children and 10 men.

He said 30 people were rescued, and added that search operations were still under way as it was not known how many people were aboard the ferry.

Col Khalil said the ferry sank because of a technical problem, and that there were not many boats in the area to rescue people.

He said more than 80 people were on the ferry when it sank.

The river’s level was high because of a rainy season that brought more precipitation than previous years.

The accident occurred on Thursday as scores of people were out in the tourist area celebrating Nowruz, which marks the Kurdish new year and the arrival of spring.

Iraqi prime minister Adel Abdul Mahdi ordered an inquiry into the accident and said that those responsible would be held accountable.

Reconstruction of Mosul, much of which was destroyed in a military campaign to recapture the city from Isis militants in 2017, has barely begun and is haphazard.

Residents say they feel abandoned by the central government, but have returned and started to rebuild their own homes. The city’s infrastructure remains largely damaged.

The accident took place to the north of the city, near a recreational area popular with families.