(CNN) -- At least 11 people were killed and more than 100 others injured after an explosion struck a subway station in Minsk, Belarus, on Monday evening, state media reported, citing President Alexander Lukashenko.
Russian President Dmitry Medvedev called the blast a "terrorist attack" and offered to help investigate who was behind the explosion, the Kremlin said in a statement. Medvedev made the remarks in a telephone call with Lukashenko, who later said at an emergency government meeting that he accepted the offer of assistance.
"I have just talked with the Russian president. Regretfully, they have much experience in this work. Get in touch with your colleagues from (Russian Federal Security Service) FSB, prosecutor's offices, the Interior Ministry, and tell them what assistance is needed," Lukashenko said, according to the Interfax news agency.
About 50 people were taken to the hospital after the incident, and more were treated at the scene "with various injuries," Belarus' state-run news agency Belta reported.
The agency later cited Belarusian Health Minister Vasily Zharko as saying that 126 were hospitalized after the attack and that 22 of them were in critical condition.
Lukashenko ordered officials to increase public transport security, according to Belta.
He also instructed security officials to investigate whether this latest blast could have any connection with an explosion in downtown Minsk in July 2008, Belta reported. That bomb went off during an open-air concert, injuring some 55 people.
"Perhaps, they are linked. Establish who could benefit in disrupting the calm and stability in the country and find out who is behind the attack," Lukashenko said, according to Belta.
The agency also reported that Lukashenko said a day of mourning would be declared in Belarus.
Rescue workers in at least 12 emergency vehicles responded to the scene, carrying the wounded away in their arms or on stretchers, Russia's Interfax news agency reported.
The blast occurred at 6 p.m., a metro police spokesman told Interfax.
CNN could not immediately reach officials in Minsk for comment.
CNN's Maxim Tkachenko contributed to this report