ROME: Up to 25 people were missing, feared drowned, on Friday after men on a Libyan coastguard speedboat attacked a packed migrant dinghy during a rescue operation off the north African state.

German NGO Sea-Watch, which is taking part in the multinational search and rescue operation in the Mediterranean, said the tragedy happened after its boat Sea-Watch 2 and a passing oil tanker were sent to help the distressed dinghy in the early hours.

As the rescue operation proceeded just beyond Libyan territorial waters north of the port of Sabrata, a speedboat bearing the Libyan coastguard insignia arrived and tried to steal the dinghy’s outboard engine, spokesman Ruben Neugebauer said.

The men, who spoke Arabic, beat some of the migrants with sticks and some clambered onto the dinghy, causing panic which resulted in one side of the boat deflating and most of the passengers ending up in the sea.

After the assailants left, Sea-Watch said it had rescued 120 people and recovered four corpses from the water.

Other bodies were seen floating but could not be recovered and it was estimated that between 15 and 25 of the people who had been on the board were unaccounted for.

Sea-Watch said in a statement that its two speedboats had been “hassled in an aggressive way” during the attack, “preventing our crew from providing life vests and medical aid to the people in need.” “All of these deaths could have been avoided but for this intervention,” Neugebauer added.

The spokesman said the NGO had no way of knowing if the attackers had any contact with the Libyan coastguard or had simply hijacked one of their boats.

But he said the incident highlighted the dangers inherent in European plans to train and equip the Libyan coastguard to be able to restrict the flow of migrant boats from the conflict-torn country towards Italy.