Counter-terrorism detectives are investigating the motive for the attacks overnight which are believed to be linked.
Counter-terrorism police in the West Midlands are investigating attacks on five mosques in Birmingham overnight.
Police responded to reports of a man smashing windows with a sledgehammer at the Jame Masjid in Birchfield Road at 2.32am, but when they arrived at the scene they discovered the attack had taken place some time earlier.
Around 42 minutes later, police were alerted to a similar attack at a mosque in Slade Road, Erdington.
Patrols were stepped up across the city and officers discovered further damage at places of worship in Witton Road, Aston, and on Broadway in Perry Barr.
A further investigation was launched after pictures emerged on social media showing smashed windows at the Mosque and Muslim Community Centre in Albert Road, Aston.
The motive behind the attacks remains unknown but West Midlands Police said it is believed they are linked.
Adil Parkar, from the Birmingham Council of Mosques, told Sky News he was “appalled” by the attacks, but not “surprised” they had taken place.