Venezuela's government says parts of the capital and seven western states were left without electricity after two generating plants had technical problems.

The blackout began at 1:30 p.m. Thursday in Caracas and lasted about an hour. It caused traffic jams in parts of the capital as street lights stopped working and office buildings were evacuated, causing hundreds of people to walk in the middle of streets because sidewalks were overflowing.

Electrical Energy Minister Jesse Chacon said frequency fluctuations caused problems in "two large generating machines" in the Andean region. He said seven of Venezuela's 23 states were affected.

The socialist country suffered major blackouts in 2012 and 2013. The administration blamed those outages on sabotage, while opponents said they were the result of government incompetence.