The death toll from an overloaded ferry that capsized on Zimbabwe’s Lake Kariba has risen to 84, police said on Sunday, after another 12 bodies were recovered from the lake. The figure stood at 72 a day earlier.

At least 18 children are among the dead. A police list showed 16 of the child victims were aged 10 or younger, with the youngest just one year old, CNN reported. Authorities had initially been unable to say how many children were aboard because passengers below ticketing age were not counted in passenger estimates.

The accident is believed to be the deadliest of its kind in Zimbabwe, Al Jazeera reported. Police said search efforts remained under way to recover people still listed as missing.

Carrying 153 on a vessel licensed for 90

The ageing vessel, operated by Zimbabwe’s Rural Infrastructure Development Agency, went down in strong waves on Tuesday while travelling from the town of Kariba to rural and fishing communities in the country’s northwest, where roads are damaged and public transport is scarce.

Estimates have put the number of passengers as high as 153 against an authorised capacity of 90. Police investigations indicate the boat was overloaded when it overturned, and the latest official figures suggest the passenger count may have been higher still. Zimbabwe’s disaster management agency has said 77 people were rescued.

Survivors told reporters that high winds whipped up choppy waves that flooded the boat shortly after it left the harbour, and that passengers urged the operator to turn back before the vessel continued into open water and rolled over, Al Jazeera reported on Saturday. A memorial service for the victims was held at Nyamhunga Stadium in Kariba on Thursday.

Lake Kariba, created by damming the Zambezi River between the late 1950s and early 1960s, is the world’s largest human-made lake by volume. It stretches more than 200km and is up to 40km wide in places, with the Zimbabwe–Zambia border running through its middle.