TEL AVIV: Prime Minister Benjamin Netanyahu said Tuesday that body parts returned by Hamas overnight were the partial remains of a hostage previously recovered in Gaza by Israeli troops almost two years ago, an announcement that threatened to rattle the tenuous, US-brokered ceasefire agreement.

Netanyahu called the return a “clear violation” of the ceasefire agreement, which requires Hamas to return all Israeli hostage remains as soon as possible. He said he will convene top security officials for an emergency discussion on Tuesday afternoon to weigh Israel’s response.

Israeli media said Netanyahu’s likely options include halting the entry of humanitarian aid to Gaza, expanding Israeli control of Gaza or carrying out airstrikes targeting Hamas leaders.

There are still 13 bodies of hostages in Gaza, and the slow recovery of those remains is posing a challenge to implementing the next stages of the ceasefire, which will address even knottier issues, such as the disarmament of Hamas, the deployment of an international security force in Gaza and deciding who will govern the territory.

Hamas has said it is struggling to locate the bodies amid the vast destruction in Gaza, while Israel has accused the militant group of purposely delaying their return. Over the weekend, Egypt deployed a team of experts and heavy equipment to help search for the bodies of the remaining hostages. That work continued Tuesday in Khan Younis and Nuseirat.