Nicolas Maduro narrowly defeated opposition leader Henrique Capriles in Venezuela's election. (OEA - OAS/Creative Commons)

Maduro, who led all polls before the election, grabbed 50.7 percent of the vote, while opposition candidate Henrique Capriles pulled in 49.1 percent. About 80 percent of eligible voters participated in the election.

Tensions escalated after polls closed as both sides accused the other of plotting fraud, USA Today reported. Capriles and his campaign claimed the government was trying to steal the election.

The 40-year-old challenger, who faulted the late president's regime for putting Venezuela on the road to ruin, posted on his Twitter account: "We alert the country and the world of the intent to change the will of the people!"

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At Andres Bello high school in central Caracas a band of about 100 Chavistas on motorcycles, many with faces covered with bandanas, harassed opposition activists who wanted to witness the vote count to ensure there was no fraud.

Some of the Chavistas tried to steal phones and cameras from people recording video of the event. The digital audio recorder of an Associated Press reporter was grabbed out of her hand.

Motorcycle-riding Chavistas have on several occasions during the campaign beaten Capriles supporters in the capital, though none apparently seriously enough to require hospitalization.

Maduro, who campaigned on a promise to continue Chavez's brand of socialism, rested his hopes on his predecessor's popularity with the working class and poor. His lead in pre-election polls had eroded over the past two weeks in a country with possession of the world's largest oil reserves. The South American nation has been afflicted with double-digit inflation, food shortages and one of the world's highest homicide and kidnapping rates.

Maduro is scheduled to be sworn in on April 19, and will serve until January 2019 to complete the six-year term Chavez would have started in January. Chavez succumbed to cancer on March 5.

Read more Neon Tommy coverage of Venezuela here.

Reach Executive Producer Danny Lee here; follow him here.