GAZA, March 12 (Xinhua) -- The Israeli naval forces arrested 11 Palestinian fishermen off the coast of southern Gaza Strip on Monday, according to the Gaza fishery union.

Nizar Ayyash, the chairman of the Gaza-based fishermen union, told Xinhua that the Israeli naval vessels surrounded a fishing boat off the coast of Rafah, arresting all fishermen on board and seizing the boat.

Under the Oslo peace agreement, signed between Israel and Palestine Liberation Organization in 1993, Palestinian fishermen are allowed to fish in an area of 20 nautical miles (37 km).

But the Israeli navy has reduced the fishing zone down to six nautical miles, and sometimes to only three nautical miles offshore, after Israel imposed a tight blockade on the enclave after the Islamic Hamas movement seized control of Gaza in 2007.

On Feb. 25, an Israeli army spokesman said the naval forces opened fire at a fishing boat sailing beyond the allowed fishing zone, killing one fisherman and wounding two others.

Last May, a Palestinian fisherman was shot dead off Gaza's shore by Israeli gunfire.

There are about 3,800 fishermen with more than 700 boats in Gaza, according to official Palestinian figures.