President Paul Kagame has sent a message of condolence to the government and people of Burundi, following the passing of President Pierre Nkurunziza.

Nkurunziza's death which occurred on Monday was announced Tuesday, June 9, by government spokesperson Prosper Ntahorwamiye.

According to a statement, he succumbed to a cardiac arrest from where he was admitted at Karusi Fiftieth Anniversary Hospital in central Burundi, where he had been hospitalised since June 6.

In his message which he posted on his Twitter handle, President Kagame noted that the government of Rwanda sends condolences to the Burundian people including the first family.

"On behalf of Gov't and my own behalf I sent our condolences to the Gov't and People of Burundi for the passing of President Nkurunziza. This also goes to the family of the President," Kagame noted.

Following the news, the Burundian government announced seven-day national mourning for the fallen president, starting Wednesday.

Nkurunziza, 55, had led the country since 2005.

He was set to step down in August following the election of Maj. Gen. Evariste Ndayishimiye on May 20.

Ndahishimiye comes from CNDD/FDD political party, which Nkurunziza was part of.