A video showing Sri Lanka's top police officer angrily assaulting an employee who refused to participate in compulsory morning meditation sessions has ignited a firestorm of controversy in the Buddhist-majority nation.

In leaked CCTV footage, Inspector-General Pujith Jayasundara can be seen shaking a lift operator by the collar and making threatening gestures after the man failed to join the meditation session at police headquarters.

Jayasundara, who has claimed prayer and Buddhist rituals helped elevate him to the top police job, raised eyebrows in February when he made daily meditation mandatory for the 85,000 officers and staff under his command.

Government spokesman Rajitha Senaratne said the incident risked further embarrassing Sri Lanka's police force, whose reputation has already been tarnished over allegations of abuses during the long-running civil war and thereafter.

"If our police chief is behaving like this, then we will have to accept when international organisations accuse our police of routinely using torture on suspects," Senaratne told reporters in Colombo.

"There are serious questions about issuing such instructions in a multi-cultural, multi-religious society like ours."

He declined say whether the police chief had himself attended the morning meditation session prior to the assault.

Jayasundara is no stranger to controversial outbursts, having been put on notice after publicly declaring he could "bend the law without breaking it", government sources said.

Police spokesman Ruwan Gunasekera said no internal disciplinary action was being taken against Jayasundara, but an investigation was under way into how the footage was leaked.

He was the first police chief appointed by an independent commission set up in the aftermath of the civil war. He can only be removed by parliament.