ROME, ITALY -- Italian police were out Wednesday hunting for 10 prisoners who escaped in the aftermath of jail riots sparked by fears over coronavirus, as authorities began to test inmates and distribute face masks.

Those still on the run were part of a group of 72 inmates who escaped on Monday from a prison in Foggia, located near Italy's southeastern coast, the justice ministry said.

They include a 36-year old man, Cristoforo Aghilar, who was arrested last October for killing the mother of his ex-girlfriend, as well as several men with links to organised crime. Nine are Italian citizens, and one Macedonian, the ministry said.

At least 6,000 prisoners took part in the riots, which broke out on Sunday across the country, Justice Minister Alfonso Bonafede told the Senate on Wednesday, which was nearly empty due to new restrictions on group assembly.

Thirteen inmates died in the riots. The last death, announced Wednesday evening by the justice ministry, was of a Tunisian inmate in Bologna who had "presumably" overdosed. A search of the inmate's cell uncovered "103 different types of tablets and 6 syringes," the ministry said in a statement.

Most prisoner deaths were due to drug overdoses after rioters stormed prison infirmaries, Bonafede said.

Forty guards were also wounded in the riots, the minister said. 

At the medium-security prison of Foggia, a few prisoners set their sheets and mattresses on fire on Monday, attracting the attention of guards. 

At the same time, a group of about 200 men managed to force open the doors of an exit corridor and some reached the outer limit of the prison and scaled the outside walls, Bonafede said. 

The prison suffered serious structural damage, he said.

Before the riots, inmates had objected to new restrictions on visits by family members designed to keep coronavirus -- which has already killed 631 people in Italy -- out of the country's overcrowded prison system.

"It's evident that so many prisoners are worried, especially in overcrowded conditions, about the impact of coronavirus on inmates' health," Bonafede said.

About 100,000 protective masks were being distributed throughout the prison system, while tests for coronavirus would soon be conducted on inmates who had recently been transferred between institutions, he said.