BAGHDAD - Iraq has exhumed the remains of 47 people believed to have been massacred by militants from mass graves in Tikrit, the human rights ministry’s spokesman said Tuesday.

“The number of remains that were exhumed so far is 47, and they were found in 11 mass graves,” Kamel Amin told AFP, adding that the number is expected to rise.

Amin said they are believed to have been victims of the infamous Speicher massacre, named for the military base near which up to 1,700 mostly Shia recruits were abducted by the Islamic State (IS) militant group last year. But DNA testing is required to confirm their identity, he said.

The killing of the recruits - which the militant group documented in photos and videos posted online - stoked widespread anger and helped rally support for the battle against IS. The mass grave sites were discovered after Iraqi forces retook the city of Tikrit last week in their biggest victory so far against IS.

IS led an offensive last June that overran large areas north and west of Baghdad, but Iraqi security forces and allied paramilitaries have succeeded in regaining significant ground.

Meanwhile, the Islamic State group has beheaded four men for armed robbery and murder in the northern Iraqi province of Nineveh, according to an online propaganda video seen by AFP Tuesday.

The undated video portrays the group, which has been steadily retreating recently from Iraqi forces backed by Iran and a US-led coalition and Iran, as still capable of maintaining law and order and dispensing justice. A masked militant in front of a large crowd to reads out over a loudspeaker the charges of which the men were convicted by the “Islamic Court in the State of Nineveh.”

A masked executioner is then shown beheading four men with a sword, after which their bodies are hung on crosses in the back of a small pickup truck. Earlier in the video, allegedly stolen money is shown being returned to its owners, who make thumbprints in a receipt book.

An IS offensive overran large areas north and west of Baghdad in June, but security forces and allied paramilitaries have succeeded in driving the militants out of much of two provinces north of the capital.

Nineveh, where the video was said to have been shot, was the first to fall to the IS-led drive and is still the militant group’s main stronghold in the country.

The militants have carried out a wave of abuses in areas they control in Iraq and Syria, including public beheadings, mass executions, enslavement and rape.