A 28-year-old man has admitted throwing a petrol bomb in a Leicester police station which injured three people.
The three were treated in hospital for cuts and bruises in the incident at the Beaumont Leys station on 3 July, Leicester Crown was told on Wednesday.
Mohammed Atif Kamal, of no fixed address pleaded guilty to arson with reckless intent and arson with intent to endanger life.
He is due before the court again on 4 September for sentencing.
The court heard Kamal filled two wine bottles with petrol, which he lit and threw, one by one, through the doors of the police station.
He was arrested minutes after the explosion.
West Area Commander, Ch Supt Steve Pitts, said: "The motive for the incident is not clear but there is no evidence that the attack was religiously or politically motivated.
"There was some excellent and at times courageous work carried out by staff and officers, in ensuring the safety of prisoners, the public and colleagues alike, co-ordinating and preserving the scene and ultimately in the apprehension and arrest of the suspect."
Leicestershire Police are now carrying out a review of security at all of its premises.