A chain of explosions Wednesday night at the country's main military hospital here apparently occurred when a butane gas tank blew up in the hospital kitchen, Sandinista authorities reported Thursday.
"The big explosion was the butane tank, definitely," said Maria Cristina Arguello, director of the government's international press office. "Up to now, the investigation we have made (and) all the information we have leads us to believe it was an accident," Arguello said, adding that the investigation is still under way.
No one was reported injured at the Alejandro Davila Bolanos Hospital, but the Red Cross said that about 150 patients were forced to leave the building.
Soldiers, policemen and witnesses at the scene had speculated that the blasts might have resulted from a bomb or other sabotage.
None of the anti-government rebel groups fighting to overthrow the leftist Sandinista government claimed responsibility for the incident.
Witnesses said three small explosions and some firecracker or gunshot-like sounds preceded the main blast at 10:50 p.m., which blew out windows and downed power lines at least half a mile from the military complex where the hospital is located.
Another strong blast followed moments later.
The El Chipote complex in the southwestern section of the capital also contains the headquarters of the General Directorate of State Security, some offices of Defense Minister Humberto Ortega, a military training school and the bunker where dictator Anastasio Somoza spent his last days before being overthrown by the Sandinistas in July 1979.
The blasts opened a 15-foot hole in a concrete retaining wall just east of the hospital.
Rubble from the explosions covered streets and buildings up to 500 yards away.