CCTV of both suspects at Salisbury train station (Image: Metropolitan Police)
Two journalists say the passport file of one of the suspects in the Salisbury nerve agent attack contains a telephone number that appears to belong to Russia's Defence Ministry.
Belligcat, an online investigative organisation headquartered in the UK, published a phone number on Friday that it said came from what it described as the passport records of Alexander Petrov.
The UK has accused Petrov and Ruslan Boshirov of the attempted murder of former spy Sergei Skripal and his daughter Yulia in March.
More than 120 British military personnel are continuing to help with the general decontamination of the city following the poisoning.
The UK believes the two men are Russian military intelligence agents.
The number does not bear a city code. Oliver Carroll of The Independent and Patrick Reevell of ABC News in the US tweeted that they called it using a Moscow prefix and the person who answered said they had reached a Defence Ministry number.
Calls to the number are no longer being answered.