“The identity of the man is being determined,” Petrenko said, adding that the committee was also looking into whether the perpetrator had any accomplices.
An unnamed source told Moscow-based station Ren TV that the attacker was a Russian citizen.
Officials have given no additional information regarding the explosive device so far.
The attacker approached officers from the north-eastern district of Moscow, the Interior Ministry said in a statement.
A criminal case has been opened against the perpetrator for the attempt on the life of a law enforcement officer and charges relating to the explosive device.
Law enforcement agencies were working in tandem to “establish all the circumstances”, the ministry added.
The two injured officers were taken to hospital “with various injuries” following the explosion.
Medical sources told news agency Tass the officers were in a serious condition.
The ministry identified the officer who was killed as 34-year-old Police Lieutenant Denis Bratuschenko, a senior inspector in the traffic police.
He had joined the force in 2019 and is survived by his wife and two children, it said.
“The leadership and personnel of the Ministry of Internal Affairs of Russia express their sincere condolences to the family,” a statement from Irina Volk, the ministry’s spokeswoman, read.
This is not the first time traffic police have been killed in an explosion in the Russian capital.
In December, two officers died after an explosive device was detonated when they approached a “suspicious individual” to detain him.