ROME (Reuters) - A total of around 20 migrants are feared to have died trying to cross the Mediterranean on Saturday, the United Nations refugee agency said, citing testimony from survivors arriving in Italy.

Seven men were found dead during Saturday’s rescues, but survivors brought to Trapani in Sicily indicated a further 13 had been lost at sea, UNHCR spokeswoman Carlotta Sami said.

“When they saw the rescuers coming there was probably some agitation,” Sami told Reuters. “Some of the people on board may have already been unwell, (the survivors) told us people were squashed, suffocated and then many ended up in the water.”

Among the people reported missing are a child, several Nigerian women, men from the Ivory Coast and possibly other men from Bangladesh, Sami said.

Saturday’s incident on the shortest route to Europe from Africa was the latest in a grim series which the International Organisation for Migration (IOM) calculates has killed more than 1,200 people so far this year.

More than 45,000 have successfully made the crossing, a more than 40 percent increase on the same period of 2016.

Most are packed into unseaworthy boats by gangs who have taken advantage of factional fighting and a breakdown in government in Libya to set up lucrative trafficking businesses.

Libya’s U.N.-backed government is asking for help to secure its chaotic south, and both Germany and Italy have called for greater European Union commitment to stabilize the region.

Sami said the UNHCR was looking into whether there had been another incident on Saturday, after Italy’s coast guard told the agency it had received a satellite call from a boat near Sabratha, in western Libya, but then lost contact with it.