In a statement, the Interior Ministry said the three were found guiltily of murder, and their execution were a necessary form of punishment, fit the crimes and will serve as a deterrent.

Medical sources at Al-Shifa hospital in Gaza City told reporters that three bodies riddled with bullet were dropped on Tuesday at the hospital. According to local news agencies, the three were identified as Amer Jundiyya, Ramii Juha and Matar Al-Shobaky.

The Hamas Interior Ministry said the men executed Tuesday were convicted killers.

One allegedly participated in the 2003 slaying of a young woman whose body was later tossed in a garbage bin. The killing provoked angry protests and calls from the public to execute the killers. The other two men were accused of murdering money changers in two separate incidents.

"They will be examples to others," Interior Ministry spokesman Ihab Ghussein told local Gaza radio. "We don't want to terrorize citizens. We want to prevent more killing." Following Arab tradition, the victims' families were contacted before the executions and asked if they would forgive the murderers, or accept compensation, Ghussein said. They refused, and the executions were carried out in front of the victims' families and Hamas officials.

While Palestinian law allows the death penalty, execution orders require a signature by Palestinian President Mahmoud Abbas, but he only controls the West Bank. He has not sanctioned executions since taking power in 2005. Hamas does not recognize Abbas' rule and says it does not need his approval to implement the death penalty.

Hamdi Shakour of the Gaza-based Palestinian Center for Human Rights said the executions were "the worst violation of the right to life." The executions appeared to be an attempt by Hamas to demonstrate control over Gaza and burnish its law-and-order credentials. With Gaza under blockade by Israel and Egypt since 2007, the Hamas government has had little to show for three years in power, except its claim that it has restored security to the once chaotic territory.

The ministry did not say how many prisoners remain on death row. Some 40 other Gaza residents are on death row, said Samir Zakout of local rights group Mezan. Hamas officials could not confirm the numbers but said they intended to carry out more executions.

- With input from agencies