Reports of a man being chased with a knife in Watford town centre sparked armed police patrols.

A member of security staff at a Market Street business, who did not want to be named, told the Watford Observer that a man had burst into the venue “shouting” and scaring customers on Saturday afternoon (March 23).

He escorted the man outside, without realising there was someone waiting for him with a weapon.

“I think the guy who ran in thought there were people in there so he thought he would be safe because the other guy was trying to stab him,” the 49-year-old said.

“But he was shouting abuse, we didn’t know what was going on, I didn’t know there was another guy.

“When I did see it, I reacted and chased him.”

The Watford resident, who has worked doors in the town for more than 20 years, believes heading straight for the would-be assailant surprised him and may have bought time for the victim to make a run for it.

After telling bystanders to get inside, he ran after both men towards Exchange Road. At the traffic lights the armed man apparently gave up the chase and split off to go in a different direction to his target and lose his own pursuer, which he did.

The security worker said: “I think he would have stabbed the victim. I don’t know if my chasing made a difference or not, you don’t know do you.”

A friend, who put him in touch with the Watford Observer, described him as a "true hero".

Watford Observer: Armed police in Market Street on Saturday.Armed police in Market Street on Saturday. (Image: Contribution)

After this point, the matter was left to the police officers who searched the area.

This morning (March 25), Herts Police confirmed they received a call claiming that a knife-wielding man was pursuing another man in Market Street at around 4.44pm.

A further report of a group of males with weapons being spotted in Wellstones, behind a row of High Street shops, then followed.

The Bedfordshire, Cambridgeshire and Hertfordshire Armed Policing Unit arrived in the town centre in response, alongside local police officers.

After searching the area, they were unable to find either the victim or any offenders.

They stayed in the area and continued “reassurance patrols” around the town centre, the force said.