ShechemSabi Berens/Flash 90

Tamer Kilani, a senior member of the Lion’s Den terrorist cell, was killed overnight Saturday in a motorcycle explosion in Shechem (Nablus), according to Palestinian Arab reports.

Some of the reports claimed that a bomb was attached to Kilani's motorcycle and that this was an Israeli operation. However, other reports said the blast was caused by a "mishap" after Kilani tried to mount an explosive device on his motorcycle and failed.

The Lion’s Den said that Kilani was "one of the most daring fighters of the organization", and threatened: "We promise [IDF Chief of Staff] Kochavi a hard and painful response."