Peruvian President Ollanta Humala has sworn in a new team of ministers in a shake-up that could lead to harsher crackdowns on social protests but will leave the country's free-market economic model in place.

Humala, who was a soldier before becoming a politician, chose Oscar Valdes, a former army officer who was his instructor in the military, to be prime minister on Monday.

Al Jazeera's Mariana Sanchez reports from the capital Lima.