Israel has admitted it was behind the assassination a Palestinian man killed when his car exploded in the Gaza Strip on Wednesday.
The Israel Defense Forces said it killed Mohammed Nimnim, whom it described as a senior member of the Army of Islam, an extremist group that kidnapped British reporter Alan Johnston in March 2007, releasing him four months later.
Nimnim was killed in a joint operation with the Shin Bet security service, the IDF said.
Hamas officials and witnesses said the 27-year-old's car exploded outside a police headquarters in the city of Gaza around lunchtime on Wednesday.
An IDF spokeswoman described Nimnim as a "ticking bomb", saying the army and Shin Bet has seized a "window of opportunity" to carry out the targeted killing. Shin Bet sources said Nimnim was involved in planning attacks on Israeli and American targets across the Egyptian border in the Sinai peninsula.
The Hamas Interior Ministry said the explosion was caused by an Israeli air strike. Earlier, Israeli media reports had suggested it may have been the result of car bomb that detonated prematurely and the IDF initially refused to confirm its involvement.
The explosion occurred during a period of relative calm between the Islamist-ruled Palestinian territory and Israel. A second Palestinian was wounded in the incident, Hamas said.
"The assumption is that it was an Israeli targeting [attack] but our investigation continues in order to determine the exact causes," a spokesman for the Hamas Interior Ministry said shortly after the attack. Witnesses said they saw a hole in the ground near the blast site, consistent with a missile strike.
In past years Israeli aircraft have often targeted Gaza militants, but the frequency of the strikes has diminished considerably in recent months. An unwritten truce has been in effect since Israel's three-week offensive in Gaza last year, aimed at halting rocket attacks.
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