Prime Minister Ranil Wickremsinghe [[WIK-rem-uh-SING-uh]] says the government had some "prior information of the attack", though ministers weren't told.
He says there wasn't an adequate response and there needs to be an inquiry into how the information was used.
On Sunday [[21/4]] afternoon, three police officers were killed during a security forces raid on a house in the Sri Lankan capital several hours after the attacks.
Police said 13 people have been arrested, all of whom are Sri Lankans.
A curfew has been put in place in Colombo and access to social media and messaging sites, including Facebook and WhatsApp, blocked.
