Updated 11.20am

AN EXPLOSION ON board a bus in the Israeli city of Tel Aviv has left a reported 17 people injured in what is being described as a terrorist attack.

At least three of casualties are thought to be seriously injured with indications from that the bomb was placed on board the bus as opposed to it being a suicide bomber

Police said the blast took place on a street which runs just behind the Kiriya, Israel’s sprawling defence ministry.

Al Arabiya reported that at least 17 people were injured in the blast while AFP said that at least 10 people had been injured.

“There are at least 10 people wounded of whom three are in serious condition,” emergency services spokesman Zaki Heller told Israeli public radio.

“There was an apparent explosion on a bus in Shaul HaMelech Street in Tel Aviv. The background and circumstances are not clear yet,” police spokeswoman Luba Samri told AFP.

TV images showed the bus with its windows blown out and its metal frame contorted from the force of the blast.

The front window was completely shattered and glass littered the floor as the wounded were loaded into ambulances by an army of medics.

A spokesman for the country’s prime minister Benjamin Netanyahu’s said it was “a terrorist attack.”

- with reporting from AFP