Bus explodes in southeast Jerusalem, 2 victims in serious condition - one victim reportedly critical. Police admit it was a bombing.

Twenty-one people were wounded in an explosion on Monday, which hit Egged bus line 12 on Derekh Hevron and Moshe Baram Street in the southeast of Jerusalem, not far from Kibbutz Ramat Rachel. Police later confirmed it was indeed a bombing attack.

Large Magen David Adom (MDA) and police forces rushed to the site. Police say 21 people were wounded in the attack, at least two of them seriously and seven moderately with the rest lightly wounded. Rescue forces evacuated the wounded to the hospital. One of the victims reportedly is in critical condition.

Police backtracked on their initial declaration according to which the blast was a terror attack, before later clarifying that an explosive had been planted on the bus, causing the explosion.

The police hesitation was cleared up by the director of the emergency care unit at Hadassah Ein Kerem Hospital in Jerusalem where the wounded were treated, who estimated that it was indeed an attack.

"Some of the wounds of the victims who arrived to us are from nails and bolts that penetrated their bodies. It gives the impression of wounds from a terror attack," determined the doctor.

Jerusalem district police initially confirmed that the 12 line bus was targeted, and said it was hit by an explosive or suicide bomber who detonated inside the bus.

Police afterwards said they had not yet completely determined that the incident was a terror attack. That about-face came after it was found that in the incident a bus empty of passengers exploded and an adjacent bus with passengers on board as well as a private car took the impact, with the injuries occurring on the second bus and car.

Police: It was a bomb

Police later announced that an explosive was indeed behind the blast, and that the bomb was placed in the rear of the empty bus.

The police statement added that they continue to check the motives behind the bombing - even though it comes in the midst of an Arab terror wave that has cost the lives of 34 victims since last September.

According to witnesses a large explosion rocked the bus which then became quickly engulfed in flames.

Before police announced an explosive had caused the blast, police spokesperson Micky Rosenfeld gave Arutz Sheva a briefing at the scene.

Rosenfeld earlier reported on Twitter: "Police units respond to possible explosion on bus in Jerusalem. Emergency units on scene."