UPDATE 3-Blasts at Tanzania military depot kill 20
Defence Minister Hussein Mwinyi told Reuters the explosions had stopped but officials had yet to determine the cause.
Some 23 munitions depots, a secondary school and two houses were razed in the chain of explosions at the Gongo la Mboto military base in Ilala district.
Tanzania's Civil Aviation Authority told Reuters the main Dar es Salaam International Airport, located about 10 km from the blast site, re-opened around lunchtime.
Aviation officials said there was no damage reported there or at the aiport on the semi-autonomous island of Zanzibar, one of Tanzania's leading tourist destinations, which was temporarily closed overnight.
The blasts scattered debris across densely populated neighbourhoods several kilometres (miles) from the military base.
"My neighbour's house was struck by debris from a rocket propelled grenade. Luckily, no one was injured because we were told to evacuate our homes," said Hassan Kondo, a resident of the Kivule area on the outskirts of Dar es Salaam.
Army officials said they were planning controlled detonations of unexploded bombs later on Thursday afternoon.
"We urge members of the public to be careful not to touch any debris or unexploded bombs at their areas. Lieutenant General Abdulrahman Shimbo, chief of staff of Tanzania's armed forces, told reporters.
"We have sent out teams to carefully retrieve these explosives," he said.
A similar explosion in 2009 at another military base in Dar es Salaam killed at least 26 people and wounded more than 700.
(Additional reporting by Nicholaus Mtenga in Dar es Salaam and Wangui Kanina in Nairobi; Editing by George Obulutsa)
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