The three men died during exchanges of fire with Israeli troops north of Beit Lahiya, near the Erez crossing, said Adham Abu Selmiya, who works for the Hamas-run health ministry.

"We found the bodies of three Palestinians who were killed in clashes at around 3:00 am (0100 GMT)," he told AFP, saying the bodies had been found after dawn and taken to Kamal Erdwan hospital in the nearby town of Jabaliya.

The identities of the men were not immediately clear, nor was it known if they were allied to any militant faction.

The Israeli military had no immediate comment on the incident.

Increased tensions about the Gaza border have raised concerns about a new Israeli invasion of the coastal enclave like the devastating 22-day offensive which began at the end of December 2008, killing 1,400 Palestinians, more than half of them civilians, and 13 Israelis, 10 of them soldiers.

However Gaza has been relatively quiet over the past 10 days, with a lower-than-normal number of rockets fired into southern Israel, military sources said.