Argentina's government called Thursday for a thorough investigation into deadly disturbances in several cities, where looters raided supermarkets and other establishments amid police protests for higher salaries.

"The full weight of the law must fall not only on the perpetrators (of the looting) but also the intellectual authors," Cabinet chief Jorge Capitanich, who was scheduled to meet Thursday with members of the Supreme Court, told reporters.

A "profound debate" is needed on police reform because the country cannot be "at the mercy of groups that seize other people's property or use extortion to press salary demands," he added.

"A deliberate action of this nature cannot be carried out in isolation. The modus operandi makes us believe this was a strategy that merits an investigation by the judiciary," Capitanich said.

The police protests began on Dec. 3 in the north-central city of Cordoba, where dozens of people took advantage of the lack of a law-enforcement presence to loot stores.

The wave of lawlessness then spread in the ensuing days to a score of provinces.

Police were patrolling the streets again after a deal was reached late Tuesday to raise pay in most provinces, although officers in the northern province of Salta on Thursday rejected a salary-hike proposal offered by local authorities.

Tensions also remained high in the neighboring province of Tucuman, where four people were killed this week in clashes involving storeowners, looters and local residents.

Thousands of people demonstrated on Wednesday in downtown San Miguel de Tucuman, the provincial capital, to demand the resignation of Gov. Jose Alperovich and an overhaul of the police brass.

Two deaths related to the disturbances also were reported in the northeastern province of Chaco and one each in the provinces of Jujuy, Cordoba and Entre Rios.

The Argentine government, meanwhile, is drawing up a plan to prevent looting on the outskirts of Buenos Aires on Dec. 19-20, the 12th anniversary of violent civil unrest and rioting that erupted amid a severe economic crisis. EFE