Dnipropetrovsk: Ukraine on Sunday published the descriptions of three men who are wanted over the series of blasts that wounded at least 26 people in the eastern city of Dnipropetrovsk.
"Three men are being sought" for their alleged implications in the four "terrorist attacks”, said the eastern city branch of Ukraine`s secret service in a statement seen by a news agency.
The suspects are aged between 30 and 45, the statement said, while no official information has emerged about what may have motivated Friday`s attacks.
An Internet user calling himself Eurobomber posted a message on Saturday on a local news website, claiming to have organised the four successive attacks with an accomplice.
The user also said he had left a letter claiming responsibility for the crime at a post office and threatened to commit more attacks if his demands were not met.
It was not immediately clear what demands the letter contained.
"The police are checking this information," an Interior Ministry source told the agency, declining any further comment because the investigation was under the country`s security service.
Ukraine is investigating a suspected terrorist attack after four bombs triggered within an hour in a busy area of the city on Friday injured 26 people, according to the Emergency Situations Ministry.
Ukrainian President Viktor Yanukovych visited victims in hospital on Saturday and announced a USD 2,50,000 reward "for information that will help solve the crime”.
The message claiming responsibility was not believed to be from the real attackers, 1+1 television channel reported on its website, however, citing official sources.
Investigators favour the theory that the attack was carried out by someone with mental health problems, wrote the Liga.Net news website.
Fourteen victims were still in hospital on Sunday, three of them in a serious condition, the Interfax agency reported, citing local authorities.
The attack has raised fresh concerns about the politically troubled former Soviet state`s ability to guarantee security six weeks away from the opening of the Euro 2012 football championship.
The event is co-hosted by Ukraine and Poland, and while no matches are to be played in Dnipropetrovsk itself, the organisers will take the UEFA cup to the industrial city in May as part of a tour.