Preston North End have announced that all their players who were arrested earlier this year in connection with alleged spot-fixing have been released from bail.

Six of the club’s players, including the captain, John Welsh, were named in a number of reports as having been arrested in April as part of an investigation being conducted by the National Crime Agency.

Keith Keane, Bailey Wright, David Buchanan, Ben Davies and Graham Cummins were the others.

On Friday Preston released a statement that said: “In April of this year a number of our players were very publicly arrested in connection with a wider investigation into ’spot fixing’ in football.

“At the time, they were bailed with a date for answering bail, subsequently set for Wednesday 30 July 2014.

“We have today been informed that all of our players have been released from bail and are no longer under any form of formal arrest procedure.”

A National Crime Agency (NCA) spokesman said: “As a result of recent adverse judicial comment during a trial where criminal proceedings were started, the NCA has decided to release from bail 13 subjects arrested in relation to a football match spot-fixing investigation so that further inquiries can be undertaken.

“We are unable to comment in more detail at this time.”

It is understood the decision was taken by the NCA after the collapse this week of a drugs trial against the former X-factor judge Tulisa Contostavlos.

The trial was halted after the judge said there were “strong grounds” to believe that the investigative journalist Mazher Mahmood – known as “the fake sheikh – had lied in the witness box.

The NCA had started its spot-fixing investigation after information was passed to it by the Sun on Sunday newspaper, which had published a story on the matter by Mahmood in December.