Local media reports say the small vessel appeared to be packed with more than 100 people.

Four women and three girls have died when a small boat carrying dozens of refugees and migrants capsized while approaching the port at one of Spain’s Canary Islands, according to Spanish emergency services.

Local media reports said the small vessel seemed to be packed on Wednesday with more than 100 people. Spanish rescuers and members of the Red Cross pulled people out of the water.

Red Cross spokesman Alexis Ramos told broadcaster RTVE there could be “more than 100 people” on the boat but he was unable to provide a figure for the number of those missing.

Spain’s maritime rescue service said the boat tipped over as rescuers began removing minors after it had arrived at a dock on the island of El Hierro. The service had initially located the boat about 10km (6 miles) from shore.

The sudden movement of people on the boat caused it to tip and then turn over, dumping the occupants into the water, the service said.

Canary Islands emergency services said four women, a teenage girl and two younger girls died in the accident. A helicopter evacuated two more children, a girl and a boy, to a local hospital in critical condition after they nearly drowned, the service added.

The Spanish archipelago located off Africa’s western coast has for years been a main route for refugees and migrants who risk their lives in dinghies and rubber boats unfit for long journeys in the open sea.

Thousands have died on the way to European territory on a treacherous journey from Africa over the Atlantic Ocean.

Nearly 47,000 people who made the crossing last year reached the Canary Islands. Most were citizens of Mali, Senegal and Morocco with many boarding boats to Spain from the coast of Mauritania.

The arrivals include thousands of unaccompanied children.