GAZA CITY, Palestinian Territories — Gaza's Hamas rulers on Wednesday executed a Palestinian convicted of collaboration with Israel, the interior ministry said, in what was the first such execution in a year.

The man, who was referred to only as A.S, was executed by firing squad after being convicted on April 19, the Hamas-run ministry said.

"This morning we executed A.S. who was convicted of collaboration with Israel," it said, adding that the death sentence was carried out in line with the law and after the approval of the authorities in Gaza.

"He was sentenced to death by firing squad on April 19 by a military court in Gaza City," the statement said, without giving further details about the specifics of his conviction.

The last time Gaza's Hamas rulers carried out a death sentence against Palestinians accused of collaboration was in April 2010, when they executed two men by firing squad -- in what was the first such execution since the Islamists seized power in 2007.

A month later, three more people were executed on charges unrelated to collaboration, human rights groups say.

Under Palestinian law, collaboration with Israel, murder and drug trafficking are all punishable by death.

By law, all execution orders must be approved by the Palestinian president before they can be carried out, but Hamas no longer recognises the legitimacy of Mahmud Abbas, whose four-year term ended in 2009.

In recent months, Hamas has arrested several alleged collaborators, and warned it would prosecute any "traitor" working for the Jewish state.

On March 30, a Gaza military court condemned a man to death and sentenced another to 15 years of forced labour for collaborating with Israel. Both judgements are subject to appeal.

Israeli security forces routinely use Palestinian informers to thwart militant attacks and assist in the assassination of top militants.