A collision between a speedboat carrying migrants and a Greek coastguard patrol vessel off the eastern Aegean island of Chios has killed at least 14 people, the coastguard said.

A search and rescue operation involving four patrol vessels, an air force helicopter and a private boat carrying divers was under way for potential missing passengers.

The coastguard said another 24 people were rescued and transported to a hospital on Chios, as were two coastguard officers who were injured in the incident. It was unclear how many of the survivors transported to the hospital had been injured.

The coastguard said it was not immediately clear how many people had been on the speedboat.

Video footage by a local news site showed at least one person being carried in a blanket from a coastguard boat moored on the side of a jetty into a waiting coastguard vehicle with blue flashing lights, as others appeared to lead two children toward the car.

The coastguard did not immediately have further information on exactly how the collision occurred, or on the identities of the casualties or the other passengers on the speedboat.

Greece is a major entry point into the EU for people fleeing conflict and poverty in the Middle East, Africa and Asia. Fatal accidents are a common occurrence. Many undertake the short but often perilous crossing from the Turkish coast to nearby Greek islands in the eastern Aegean.

But increased patrols and allegations of pushbacks – summary deportations without allowing for asylum applications – by Greek authorities have reduced crossing attempts.

Greece, along with several other EU countries, has been tightening its regulations on migration. In December, the EU was overhauling its migration system, including streamlining deportations and increasing detentions.