KIEV, Ukraine (AP) — Opposition lawmakers in Ukraine are suggesting that President Viktor Yanukovych's government may be behind a series of blasts in an eastern city that injured at least 27 people.

Four blasts within minutes Friday rocked the center of the Ukrainian city of Dnipropetrovsk in what prosecutors believed was a terrorist attack. Nine children are among the injured.

But deputy parliament speaker Mykola Tymenko, a member of opposition leader Yulia Tymoshenko's party, says he "does not rule out" that senior government officials were involved in organizing the blasts. Tomenko says the government may be using the attack to deflect the world's attention from Tymoshenko.

Tymoshenko, 51, the country's top opposition leader, has been on a hunger strike for a week after she was allegedly violently beaten by prison guards.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

KIEV, Ukraine (AP) — Four blasts within minutes rocked the center of the eastern Ukrainian city of Dnipropetrovsk Friday, injuring at least 27 people, including nine children, in what prosecutors believed was a terrorist attack, officials said.

Emergency Situations Ministry spokeswoman Yulia Yershova said the first blast occurred at a tramway stop in the center of Dnipropetrovsk, injuring 13 people. The second injured 11 people near a school, including the nine children, while the third wounded three near a railway station.

A fourth blast was also heard in the city center, Yershova said. It was unclear whether anybody was injured.

Interior Minister Vitaly Zakharchenko and the deputy heads of the Prosecutor General's Office and the national security service were flying to Dnipropetrovsk. Prosecutors' spokesman Yuri Boichenko said investigators are treating the blasts as a terrorist attack.

President Viktor Yanukovych called the explosions "yet another challenge for the whole country," and said that Ukraine's best investigators will be working on the case, according to the Interfax news agency. "We will think of a worthy response."

In January 2011, two pre-dawn explosions outside an office of a coal mining company and then a shopping center in the eastern city of Makiyivka caused no casualties.

The authorities then received letters demanding money in exchange for an end to the blasts. The perpetrators were later detained and sentenced to lengthy prison terms.