BAGHDAD, Iraq, AP -Two separate car bomb explosions killed at least 21 people and wounded more than 50 in the capital on Thursday, police said.

In downtown Baghdad, a suicide bomber detonated a vehicle at the entrance of a major crimes unit run by the Interior Ministry in Karradah, killing at least 15 people and wounding more than 30, police said.

Another bomb outside a Shiite Muslim mosque in the mixed Shiite-Sunni neighborhood of Shurta in southwest Baghdad killed at least six people and wounded 20, police said.

Roadside bombs targeting police patrols also killed four people in Baghdad and at least one in the nearby city of Iskandariyah, police said. Dozens of others were wounded.

In the crimes unit attack, it was not immediately clear how many of those killed were bystanders and how many were employees of the unit, which investigates large-scale crimes, police Lt. Col. Falah al-Mohammadawi said.

In the roadside blast in Baghdad’s mostly Sunni Muslim neighborhood of Azamiyah, two policemen and two bystanders were killed, according to police Lt. Ahmed Mohammed Ali. At least seven others — two policemen and five civilians — were wounded, he said.

Another bomb in Karradah wounded four civilians but no police in the district, which is mostly Shiite but has a large Sunni minority.

In Iskandariyah, 30 miles south of Baghdad, a roadside bomb killed one policemen and wounded two pedestrians, police said.

Back in the capital, another civilian was seriously wounded by an Iraqi army patrol that was shooting in the air to clear traffic in the western neighborhood of Yarmouk, police said.