Three men have been charged with terrorism offences after a police operation in which firearms were found in a car stopped by police on the M1.

West Midlands Police said Jewel Uddin 26, Omar Mohammed Khan, 27, and Mohammed Hasseen, 23, would all appear at Westminster Magistrates' Court to answer the charges.

The men, all from Sparkhill in Birmingham, were arrested by counter-terrorism officers last Tuesday. Four other men arrested in connection with the inquiry remain in custody, West Midlands Police said.

A police spokeswoman said the Crown Prosecution Service had advised that Khan, Uddin and Hasseen should be charged under Section Five of the Terrorism Act 2006 with engaging in conduct in preparation for an act or acts of terrorism, with the intention of committing such acts.

The alleged conduct between May 1 and July 4 this year includes the manufacture of an improvised explosive device, the acquisition of firearms and other weapons, and the purchase of motor vehicles connected with the charges.

The spokeswoman said officers had until Wednesday to charge, release or apply for a warrant of further detention for three of the other four men who remain in police custody. The fourth man can be held until Thursday.

Uddin, Khan and Hasseen were among seven men arrested over three days last week in Birmingham, Smethwick in the West Midlands, and Dewsbury in West Yorkshire. The arrests followed a routine stop of a vehicle by police on the M1 in South Yorkshire on Saturday June 30.

The car was impounded on suspicion of having no insurance and firearms, offensive weapons and other material were later found inside, prompting police inquiries to trace and arrest its driver.

Those who remain in custody are a 24-year-old from Moseley, Birmingham; a 22-year-old man from Alum Rock, Birmingham; a 22-year-old from Smethwick, and a male aged 43 from the Kirklees area.

In a statement issued last Friday, police confirmed that two firearms had been recovered along with a small amount of ammunition.