Authorities believe all four men who tried to plant bombs in London's transit system on July 21 are now in custody. The following is a breakdown of who the men are, according to media reports:

Suspect #1: Yasin Hassan Omar, 24, origin Somalia; was arrested in Birmingham on Wednesday. According to police, he tried to bomb Warren Street tube station.

Suspect #2: Muktar Said Ibrahim (also known as Muktar Mohammed Said), 27 yrs old, origin Eritrea, came to Britain 1990; was arrested today in London, according to police. Allegedly tried to bomb the bus in Hackney.

Suspect #3: Name, age, nationality unknown; was arrested today in London, according to police. Allegedly tried to bomb Oval tube station. Seen running away in a New York sweatshirt.

Suspect #4: Osman Hussein, 27, origin Somalia, naturalized British citizen; was arrested today in Rome, according to the Italian Interior Minister. Allegedly tried to bomb Shepherd's Bush train; later photographed escaping on a bus.

The Times of London contributed to this report.