London (CNN) -- Three men charged with terror offenses appeared in court in London Wednesday, West Midlands police said, bringing to six the number charged in the alleged manufacture of a homemade bomb.
Prosecutors have recommended all six suspects be charged with engaging in conduct "in preparation for an act or acts of terrorism with the intention of committing such acts," the police statement said. The purported activity took place between May and July.
"That alleged conduct includes the manufacture of an improvised explosive device, the acquisition of firearms and other weapons, and the purchase of motor vehicles connected with their plans."
Two of the three men who appeared in court Wednesday are aged 22 and the other is 24 years old.
The other three men, from Birmingham, England, were charged and appeared at Westminster Magistrates Court Tuesday and have been remanded in custody. They were named by police as Jewel Uddin, 26; Omar Mohammed Khan, 27, and Mohammed Hasseen, 23.
Seven men were arrested last week in a series of raids led by the West Midlands Counter Terrorism Unit.
The seventh suspect, a 43-year-old man from West Yorkshire, was released Tuesday night without charge, West Midlands police said.
Authorities said the investigation had no connection to the upcoming London Olympic or Paralympic Games.
CNN's Laura Smith-Spark contributed to this report.