Story highlights Three Palestinians are executed in Gaza, the Hamas government says

One is put to death for collaborating with Israel, Hamas says

Two others are hanged as convicted murderers

Rights groups have previously highlighted serious concerns over due process in Gaza

Three Palestinians were hanged in Gaza on Saturday, one of them for "collaborating" with the Israelis, the territory's ruling Hamas government said.

The other two were convicted of murder, the Ministry of Interior and National Security statement said. One was also found guilty of one count of sodomy with a child under 16.

The sentences were carried out according to legal procedures and all three had exhausted their right to appeal, the statement said.

Hamas, a militant Islamist group, has controlled Gaza since 2007, when it seized power from the Fatah-dominated Palestinian Authority after a short-lived coalition government failed. Hamas had won legislative elections in January 2006.

Following the execution of two Palestinians last summer, also on charges of collaborating with Israel, rights group Human Rights Watch urged Hamas to impose a moratorium on the death penalty.

"Hamas should recognize that the death penalty is cruel and inhuman and end it, even for serious national security crimes," Joe Stork, deputy Middle East director at Human Rights Watch, said in a statement at the time.

"At the very least, Hamas should impose a moratorium on capital punishment due to consistent, credible allegations of coerced confessions and other serious due process violations in Gaza."