Pope Francis has expressed sorrow over the 170 people feared drowned in recent days in the Mediterranean Sea.

The UN refugee agency has said 117 died or were missing after a smuggler’s dinghy sank off Libya on 18 January and that 53 others died when another boat capsized in the western Mediterranean a few days earlier.

Speaking in St Peter’s Square in Vatican City on Sunday, Francis said those who drowned had looked for better lives and were “victims, perhaps, of human traffickers”.

The pope said: “Let us pray for them and for those who have the responsibility for what happened.”

Flavio Di Giacomo of the International Organization for Migration (IOM) said on Saturday that “unfortunately about 120” people were reported by survivors to have been on the overloaded smugglers’ dinghy when it was launched from Libyan shores on Thursday evening.

“After a few hours, it began sinking and people began drowning,” Di Giacomo said. Among the missing are 10 women and two children, including a two-month-old baby, he said, and survivors indicated those on the boat came from Nigeria, Ivory Coast, Gambia and Sudan.

Since last year both Italy and Malta have cracked down on charities whose boats aim to rescue people from traffickers’ unseaworthy boats.

The Italian president, Sergio Mattarella, who has urged the government to show more compassion for migrants, on Saturday expressed his “deep sorrow for the tragedy that has taken place in the Mediterranean”.

The prime minister, Giuseppe Conte, who heads Italy’s populist government, told reporters he was shocked by reports of the sinking and vowed Italy would continue to combat human traffickers.

The three survivors of the sinking were rescued by an Italian navy helicopter on Friday afternoon, the navy said.

The navy said when its patrol plane first spotted the sinking dinghy it had about 20 persons aboard. The plane’s crew launched two life rafts near the dinghy, which inflated, and a navy destroyer 100 nautical miles (185km) away sent a helicopter to the scene.

That helicopter rescued the survivors, two from a life raft and one from the water, the navy said, adding that all had hypothermia.

According to the IOM, at least 2,297 people died at sea or went missing trying to reach Europe in 2018. In all, 116,959 migrants reached Europe by sea routes last year, it said.