Jeff Stewart stepped in when a thief attempted to escape on a bicycle in Southampton on Wednesday.
In a statement, a Hampshire Constabulary spokesman said: “The thief, 29-year-old Mohamed Diallo, fell off the bike during his attempts to flee, before officers pounced to make their arrest.
“To their surprise, local TV legend Jeff Stewart, who played PC Hollis for 24 years in The Bill, came to their aid by sitting on the suspect’s legs while officers put him in cuffs.
“In policing you should always expect the unexpected, but this really wasn’t on The Bill for this week.”
The Bill was broadcast on ITV between 1984 and 2010 and featured the fictional lives of police officers from the Sun Hill police station in east London.
Mr Stewart, who was among the original cast, appeared in more than 1,000 episodes as PC Hollis.
In praising Mr Stewart’s actions, the force said: “Long since retired from Sun Hill station – but he’s still got it.”
Police from the Bargate Neighbourhoods Policing Team were alerted by staff at a Co-op store in Ocean Way to a suspected shoplifter on Wednesday.
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Mohamed Diallo, 29, of Anglesea Road, Southampton, was subsequently charged with five offences of theft relating to coffee, alcohol and food from the Co-op and two other Sainsbury’s stores on three dates in April and July.
He pleaded guilty at Southampton Magistrates’ Court on Thursday and was bailed to be sentenced on August 29.
