(CNN) -- Deadly explosions ripped through two passenger buses in Nairobi, Kenya's capital, on Sunday, killing at least three people and injuring a number of others.
Kenyan police reported three people were killed and seven injured in one bus explosion, but they have not yet confirmed the second blast.
Police are treating the incident as a terrorist attack, but there were no immediate suspects, spokeswoman Zipporah Mboroki said Sunday.
The Kenya National Disaster Operation Center confirmed explosions on two buses.
The agency tweeted that two people were killed and 62 injured, including 20, who were in critical condition.
Kenya's Interior Ministry reported that of the 20 people critically injured in the attacks, nine were women, six were men and five were children.
The buses were on Thika Highway, one near the Safari Park Hotel, the other near the Homeland Inn, when the explosions occurred, according to a tweet from the NDOC.
Pictures from the scene show the buses were still mostly intact, but the windows were blown out of both vehicles. One of the buses had a piece of its side missing and part of its front bumper.
Kenyan police said they will have more information on the deadly attack at a news conference Monday.
CNN's Jo Shelley, Elwyn Lopez and Josh Levs contributed to this story.