Police are continuing to search two properties in Newport over the Parsons Green terror attack.
Earlier a 48-year-old man arrested on Wednesday from West Street has been released without charge.
Four other people, including two from Newport remain in police custody.
A 20-year-old man was arrested at an address in the Road area of Cardiff earlier this morning.
18-year-old Ahmed Hassan of Sunbury, Surrey, has been charged with attempted murder.
The 25-year-old, known locally as Bilal, was arrested on Tuesday in Newport. Two men were also arrested the following morning in the city.