A massive car bomb ripped through a used car market in the south of Iraq's capital Thursday, killing more than 50 people in the deadliest such attack this year, security officials said.

The explosion, which sent a thick plume of dark grey smoke billowing into the sky above Bayaa neighbourhood, sowed carnage and caused extensive destruction.

“A terrorist car bomb attack struck near car dealerships in Bayaa,” a spokesman for the Baghdad Operations Command said in a statement.

An interior ministry official gave a death toll of 52 and said that more than 50 other people were also wounded. Hospital officials confirmed the figures.

He said the emergency services were struggling to cope with the scope of the attack, which ripped through the busy car market at around 4:15pm (1315 GMT), and warned that the death toll may yet rise.

Security officials could be seen inspecting the site before the sun went down, while some distressed civilians searched for relatives and others took pictures with their mobile phones of the large crater caused by the blast.

“There are so many victims, not just one or two,” said Nasser, a young man wearing blood-stained surgical gloves who was near the site of the explosion and rushed to the scene to help the wounded.

“There was one here, we carried him,” he said, pointing to a spot behind him.

The site of the bombing is an open space used as a second-hand car market where hundreds of private sellers park their vehicles and wait all day to discuss prices with prospective buyers.

Deadliest bombing since Karrada

“Just the cars, you can be sure of that, there's always two or three people standing next to each car,” Nasser said, explaining the high toll.

The explosion occurred in the same neighbourhood where a car bomb blast killed at least four people on Tuesday. At least 11 people were also killed in a suicide car bomb attack claimed by IS on Wednesday on the edge of Sadr City, a northern neighbourhood of the Iraqi capital that has been repeatedly targeted.

Baghdad was rocked by a wave of deadly suicide bombings during the first days of 2017 but relatively few explosions had been reported since then until this week.

Thursday's blast was the deadliest to hit Baghdad since a huge truck bomb attack claimed by IS set two shopping arcades in the Karrada district on fire and killed more than 320 people in July last year.