West Midlands police said that detectives and counterterrorism officers have already started investigating. The four incidents "are being treated as linked,” according to a police statement.
"Neighbourhood officers are working closely with mosques around the West Midlands today," the force said.
The police were alerted in early morning Thursday after a man was spotted breaking a window with a sledgehammer in one of the moques.
"Since the tragic events in Christchurch, New Zealand, officers and staff from West Midlands Police have been working closely with our faith partners across the region to offer reassurance and support at mosques, churches and places of prayer," West Midlands Police Chief Constable Dave Thompson said in a statement.
"At the moment we don't know the motive for last night's attacks," Thompson added. "At difficult times like this, it is incredibly important that everyone unites against those who seek to create discord, uncertainty and fear in our communities.”
Shabana Mahmood, a member of parliament for Birmingham said the attacks were "truly terrible” and "I would urge all residents to remain calm and call [the police] with any info you may have."
"We were deeply horrified to hear a number of mosques were vandalised during the early hours of this morning. Birmingham's mosques are a place of worship, serenity and a source of peace and tranquillity. We are appalled by such acts of hate/terror,” said the Birmingham Council of Mosques.