Protester disrupts start of Cuba's annual May Day parade

A security officer yells "Long live Fidel! Long life Raul!" as he and other plain clothed security officers carry away a man who ran waving a U.S. flag moments before the start of the May Day march in Havana, Cuba, Monday, May 1, 2017. Monday's protest was a surprising breach of security at a government-organized event where agents line the route. (AP Photo/Ramon Espinosa) (The Associated Press)

A man runs waving a U.S. flag, chased by security, moments before the start of the May Day march in Havana, Cuba, Monday, May 1, 2017. Plainclothes officers struggled to control the man but eventually lifted him off the ground and hauled him away in front of foreign and Cuban journalists covering the parade. (AP Photo/Ramon Espinosa) (The Associated Press)

Security officers escort away a man who ran waving a U.S. flag moments before the start of the May Day march in Havana, Cuba, Monday, May 1, 2017. Monday's protest was a surprising breach of security at a government-organized event where agents line the route. (AP Photo/Desmond Boylan) (The Associated Press)

A protester has briefly disrupted the start of Cuba's largest annual political event, sprinting in front of May Day marchers with a U.S. flag before being tackled and dragged away.

President Raul Castro watched along with other military and civilian leaders and foreign dignitaries as the man broke through security and ran ahead of the tens of thousands in the pro-government march.

Plainclothes officers struggled to control the man but eventually lifted him off the ground and hauled him away in front of foreign and Cuban journalists covering the parade.

Monday's protest was a surprising breach of security at a government-organized event where agents line the route.

Castro has said he will step down as president in February, making this his last May Day parade as head of state.