A series of explosions rocked the city of Bata in the central African nation of Equatorial Guinea on Sunday, killing at least 20 people, news reports said, and most likely injuring untold more.

The Reuters news agency quoted a local television station, TVGE, as saying that at least 20 people had been killed in the blasts. Their cause was not immediately known.

The country’s Ministry of Health and Social Welfare said in a statement that there was a health emergency in Bata as a result of explosions at a military barracks. Many were missing under the rubble, it said.

The ministry said that rescue workers in the country, on the west coast of Central Africa, were bringing those injured to at least three hospitals in the city. Officials appealed for blood donations.

It said the number of injured people could be in the hundreds.