Six Palestinians were trapped and another was missing Thursday after a Gaza smuggling tunnel collapsed, a local civil defence official said.

He described the underground passage from the southern Gaza town of Rafah into neighbouring Egypt as a "trade tunnel".

The cave-in, the sixth since January.

Authorities have spoken to one of the trapped men by mobile telephone and rescue efforts are under way, he added.

Since January 26, 12 Gazans have been killed in five separate tunnel collapses.

Such collapses have previously occurred in the coastal strip, which is under an Israeli blockade and has seen three wars with Israel since 2008.

During a 50-day Israeli assault in 2014, Israeli warplanes destroyed a large part of the underground network of tunnels used by Gazans.

Hamas has reportedly rebuilt tunnels destroyed in the 2014 conflict that Israeli officials say could be used to carry out attacks.

Israel's blockade severely restricts the movement of people and goods into and out of the enclave.

*The story was edited by Ahram Online.