Leszek Szymański/PAP

Two men have been arrested in connection with the broadcasting of radio stop signals to trains which disrupted rail services over the weekend in the north-west of Poland.

Tomasz Krupa, spokesman for Podlasie Police, said the two men, aged 24 and 29, were detained in the house of one of them after 1 p.m. on Sunday.

Ham radio equipment was also found in the premises.

Private radio station RMF FM reported that the two men are believed to have broadcast a signal at various intervals, activating the emergency brakes on a number of passenger and freight trains.

Nobody was hurt in the incidents but they raised the possibility that rail traffic may have been sabotaged.

Stanislaw Zaryn, deputy coordinator of the Polish intelligence services, referring to the case on Radio Three, said that the security services must check “exactly what these people did”.

“We are continuing to investigate the situation. We do not have all the information yet. Some patience and calm are needed here,” he said.

“The ABW (Internal Security Agency) must now get involved in investigating this type of thing, but it is not certain that we are talking about some foreign state funded Machiavellian operation,” he added.

The incidents on the railways, Zaryn said, “may result from the operations of, for example, the Russian secret services, so such things cannot be underestimated.”