WASHINGTON, Nov 10 (Reuters) - Special counsel Robert Mueller is investigating whether U.S. President Donald Trump’s first national security adviser, Michael Flynn, was involved in an alleged plan to seize a Muslim cleric and deliver him to Turkey in exchange for millions of dollars, the Wall Street Journal reported on Friday.

Under the plan, Flynn, who was fired by Trump after just 24 days in the job, and his son, Michael Flynn Jr, were to receive up to $15 million for forcibly removing Fethullah Gulen from his U.S. home and delivering him to the Turkish government, people familiar with the investigation told the Journal.

The alleged plan emerged during Mueller’s wider investigation of possible Russian interference in the 2016 presidential election and any collusion by the Trump campaign.

Turkish President Recep Tayyip Erdogan accuses Gulen of instigating a failed coup in July 2016 and wants him extradited to Turkey to face trial. Gulen has denied any role in the coup.

A spokesman for Mueller’s team declined to comment on the report on Friday.

Flynn is a central figure in Mueller’s investigation because of conversations he had with then-Russian Ambassador Sergei Kislyak last year and because he waited until March to retroactively register with the Justice Department as a foreign agent for the work he did for a Turkish businessman.

The Journal reported that FBI agents asked at least four people about a December meeting in New York where Flynn and Turkish government representatives discussed removing Gulen, according to people with knowledge of the FBI’s inquiries.

The December meeting about Gulen was also reported Friday by NBC, which cited people familiar with the probe. The group also discussed how to set free a Turkish-Iranian gold trader, Reza Zarrab. Zarrab is in prison in the United States on federal charges that he helped Iran skirt U.S. sanctions, NBC said.

A Reuters report on Oct. 26 said one of Flynn’s business associates, former CIA Director James Woolsey, pitched a $10 million contract to two Turkish businessmen to help discredit Gulen while Woolsey was an adviser to Trump’s election campaign.

Woolsey was a member of Flynn’s firm, the Flynn Intel Group, according to a Justice Department filing by the firm and an archive of the company’s website.

Mueller’s team has also interviewed White House senior policy adviser Stephen Miller, the highest-level Trump aide known to have spoken with investigators, CNN reported on Thursday.

(Reporting by Doina Chiacu; Editing by Bernadette Baum)