Egyptian naval police shot and wounded two Palestinian fishermen and detained five off the Gaza Strip on Friday, medics said, an incident that hinted at increased tension between Gaza's Islamist Hamas rulers and Cairo.

Fishermen from Gaza have often brought in catch from Egyptian territory to sidestep restrictions imposed by Israel's naval blockade of the enclave. But Egypt has grown less tolerant of this practice since Islamist president Mohammed Morsi was toppled by the military almost two months ago.

The group of seven Palestinian fishermen were sailing west of the southern Gaza border town of Rafah toward Egyptian waters when the forces opened fire at them, Gaza hospital officials said. Egyptian authorities had no immediate comment.

The wounded pair avoided arrest and were only lightly hurt, hospital officials in Gaza said.

Relations between Hamas and Egypt have deteriorated markedly since Morsi was removed by the Egyptian military on July 3 after weeks of mass unrest against his Islamist rule. Hamas is an offshoot of Morsi's Muslim Brotherhood

Egyptian officials have accused Hamas of aiding Islamist militants in Egypt's widely lawless Sinai peninsula bordering Gaza. Hamas denies this.

Citing security concerns, Israel, Hamas's arch-adversary, maintains a naval blockade of the enclave and imposes a limit of six nautical miles (5.5 to 11 km) on the distance that fishermen can sail out to sea.

Israeli forces have regularly shot at Gaza boats seen as trying to breach the blockade, but there was no previous record of the Egyptians opening fire.

Gaza fishermen say that the limited fishing zone imposed by Israel is not big enough to meet the demands in the enclave and have often brought fish back from Egypt, either by boat or through smuggling tunnels.

Since Morsi's ousting, Egyptian authorities have warned Gaza fishermen against entering Egyptian territorial waters.

It could not be confirmed whether the fishermen shot at on Friday were attempting to cross into Egyptian waters.