LAGOS -- Death toll from multiple bombings that hit Maiduguri in northeast Nigeria's restive Borno state capital has exceeded 50, local reporters told Xinhua Monday.

Most of the journalists who spoke with Xinhua on phone said the death toll might be higher as some other victims were taken to the Umaru Shehu hospital, where the casualty figures are presently not clear.

Security sources said the first explosion was targeted at a Mosque in Ajilari cross at the time of the late evening prayers on Sunday.

Another bomb is said to have exploded at a mini business district and the third explosion occurred in a game center in the area where people pay to play computer games and charge their mobile phones.

The three blasts come a day after a new audio message purportedly from Boko Haram leader Abubakar Shekau accused the Army of lying about successes against the militants.

Reacting to the audio message, Col. Sani Usman, Nigeria's military spokesperson, describes Shekau's comments as "the rant of a drowning man", adding that efforts are on to ascertain if that is Shekau's voice.

He said the Nigerian military would not be deterred in its determined efforts of defeating Boko Haram terrorists in the shortest possible time.

The military spokesperson added that the attacks signify high level of desperation on the part of the Boko Haram terrorists.