It is not clear if the hacker posted anything on Mr Obama's Twitter page

A Frenchman who police say hacked Twitter accounts belonging to US President Barack Obama and celebrities could face jail.

The unemployed 25-year-old was arrested on Tuesday after an operation lasting several months, conducted by French police with agents from the FBI.

The 25-year-old is said to have hacked into the micro-blogging website, by simply guessing users' passwords.

The suspect reportedly targeted other celebrities, including Britney Spears.

After being questioned by police, he was ordered to appear at court in the central French city of Clermont-Ferrand on 24 June.

Hacking into a database in France is a crime which can carry a two-year jail term.

The suspect, who used the pseudonym "Hacker Croll", had no specialist training, Adeline Champagnat, head of the French central office against online fraud, told Reuters news agency.

He gained access to Twitter accounts by simply working out the answers to password reminder questions on targets' e-mail accounts, according to investigators.