LJUBLJANA, Dec. 30 -- Slovenia strongly condemned on Monday successive terrorist attacks in the Russian city of Volgograd which killed at least 27 people.

The attacks on Sunday and Monday were "atrocious acts for which there can be no justification," the Slovenian Foreign Ministry said in a statement.

"Our sincere condolences go to the families of all those who lost their lives and to the Russian authorities, along with best wishes for a prompt recovery of those injured."

The statement also added that those responsible for the horrible attacks must be brought to justice.

At least 10 people were killed and 28 others injured in a trolley bus blast in Volgograd on Monday. On Sunday, a suicide bombing ripped a railway station in the same city, killing 17 people and injuring 45 others.