Most Hamas members have left Syria, with only several remaining in the country. Tensions have escalated recently between Hamas and the Syrian regime after most of the party’s political leaders fled the country due to the violence.

According to Izzat a-Rashak, a member in the Hamas political bureau, anonymous persons killed Kamal Ghanaja (who also goes by Nizar Abu Mujhad), in what was termed as a “criminal act”.

Rashak announced the killing in a statement on Facebook, and said that the movement is investigating the killing in order to find out who was behind it. Rashak further stated the Ghanaja was a member of Hamas for many years who served his movement and his people, adding that his blood “shall not be shed in vain”, AFP reported.

Ghanaja was also a former deputy of Mahmoud al-Mabhouh, a top Hamas official who was assassinated in a Dubai hotel room two years ago.

Hamas in a press statement on its website on Wednesday evening expressed its “sadness and pain of the martyrdom of  Kamal Hosni Ghanaja (Nizar Abu Mujahid), who was assassinated at his home in the Syrian capital Damascus by unknown.”

Hamas explained “that the movement is conducting an investigation to find out who is behind this heinous crime.”

When asked by Army Radio to comment on the reported killing, Defense Minister Ehud Barak refused to deny or confirm Israeli involvement in the incident, only saying: “According to the background published [about], he would not mourn the Hamas member because he was not “one of the righteous of his generation,” Haaretz reported.