At least 21 people were injured Monday after a bomb exploded on a public bus in Jerusalem, Israeli police and medics said.
Explosive experts from the Israeli police confirmed that an explosive device on the bus caused the blast, police spokesman Micky Rosenfeld tweeted.
Israeli media speculated that a Palestinian suicide bomber was to blame. The possibility of a technical defect was also being investigated.
The explosion occurred in the rear part of the bus, Rosenfeld said. Some of the injuries occurred after a nearby bus caught fire.
All of those injured, including two with serious injuries, were taken to hospital for treatment.
Bus bombings were common in Israel during the intifada, or Palestinian uprising, more than 10 years ago.