Extra officers continue to be deployed across the transport network in the aftermath of the Parsons Green terror attack.

British Transport Police (BTP) said an enhanced level of highly visible patrols were both on board trains and at key stations across the UK on Monday (September 18) to provide public reassurance.

In addition, specialist counter terrorism officers are working closely with police forces to deter any further acts of terrorism.

The increase in police presence has been in force since the day of the attack - Friday (September 15) - in which 30 people were injured after a bomb blast.

Parson Green Terrorist incident

The UK threat level has since been lowered from critical to severe, which means an attack is "highly likely."

Witnesses have told how they "ran for their life" after a white cannister exploded

Op Temperer, enacted by the Prime Minister, has allowed extra firearms officers from the Ministry of Defence to patrol alongside BTP, the force said.

Assistant Chief Constable Robin Smith, from BTP, said: “Undoubtedly the terrorist incident at Parsons Green Tube station would have caused concern amongst the public.

Parsons Green Terror alert

"Therefore, we quickly took action to step up patrols and provide an enhanced level of visibility both on trains and at stations nationally.

“In the coming days, we will be maintaining this enhanced level of visibility throughout the country.

Parsons Green terror attack: Arrests and raids

"This means that those members of the public travelling to work can feel at ease knowing we’re out there keeping them safe."

The public are urged to remain "alert, and not alarmed".

Two suspects arrested in connection with the terror attack in west London remain in police custody.

Huge armed police raids have been carried out at two homes, in Sunbury and Stanwell in Surrey, with residents evacuated in both areas.

The search of a lavender house on Cavendish Road continues

If anyone sees something that does not look right or any suspicious behaviour is urged to contact BTP; text 61016 or call 0800 40 50 40.

Alternatively call the anti-terrorist hotline on 0800 789 321.

Dover Port, where detectives investigating the Parsons Green bombing have arrested an 18-year-old man on suspicion of a terror offence

Officers can be stopped if you wish to report any suspicious behaviour or unusual activity.

In case of an emergency, always ring 999.