At least 18 people died Saturday and 50 others were wounded in four car-bomb explosions in different Shiite-majority areas of the Iraqi capital, police officials told Efe.

In two of the attacks, one in the southern area of Abu Deshir and the other in the southwestern district of Al Baia, 13 people were killed and at least 37 injured, the source said.

A car parked in Al Baia blew up in front of a Shiite mosque.

Police officials said the third bomb exploded in the Al-Yihad neighborhood in southwestern Baghdad, wounding five civilians, one of whom is in critical condition.

The last attack was carried out in the Al Kazimiyah district on the Iraqi capital's north side and killed at least five people and left another 17 injured.

The four blasts caused significant material damage to nearby buildings, stores and parked cars.

Terrorist attacks and violence against Shiite Muslims and security forces are on the rise in Iraq.

These attacks coincide with an offensive by Sunni insurgent groups, including the radical Islamic State of Iraq and Syria, against the army and other forces loyal to the government of Prime Minister Nouri al-Maliki, a Shiite.

Since June 10, when they occupied Iraq's second-largest city, Mosul, the insurgents have gone on to control various parts of the country, with ISIS declaring an "Islamic caliphate" in territories it has taken over in Syria and Iraq while expanding its conquests in both countries. EFE