(Refiles to clarify event was opening ceremony of tournament, not presidential inauguration, in 3rd paragraph)
By Andrew Cawthorne
CARACAS, Feb 5 (Reuters) - A Venezuelan opposition party demanded on Wednesday that President Nicolas Maduro's government release seven protesters arrested following a weekend fracas outside the hotel of a visiting Cuban baseball team.
The Caribbean Series baseball tournament between the region's top clubs, being held on Venezuela's Margarita Island, has this year become a lightning rod for anti-Maduro activists.
Maduro was booed by some in the stadium during the president's ceremonial opening of the tournament on Saturday, according to videos shown by local media. Foes accuse Maduro of being a stooge for Cuban President Raul Castro and his brother Fidel.
Seven people are still being held after a protest on Sunday outside the hotel being used by Cuba's Villa Clara team. Banners decried Venezuela's economic problems and its treatment of critics.
"We are not Cuba! Remove the chains!," read one placard.
Venezuelan authorities accused the demonstrators, whom witnesses said numbered about 200, of pelting the Cuban team's bus with objects and stopping the players from entering the hotel.
"It's unacceptable that they have tried to assault sportsmen. That is pure fascism. They're going to prison," said a furious Maduro on the night of the incident.
But Leopoldo Lopez, whose hardline opposition party "Popular Will" is trying to whip up street protests against Maduro, said on Wednesday that the detainees were victims of his pique.
"These young people are behind bars for raising a banner. There was never any aggression toward sportsmen or anyone else. I challenge the cowards to show any evidence," Lopez said at a news conference in Caracas calling for their release.
"They say Maduro himself gave the order in retaliation for the boos he received on Saturday ... Maduro's plan is to spread fear via repression so that we do not take to the street."
Calls by Lopez and another opposition leader, Maria Corina Machado, have led to small, sporadic protests around the country in recent days. But they have also split the opposition, with other major figures such as two-time former presidential candidate Henrique Capriles preferring a more moderate approach.
Maduro narrowly beat Capriles in a 2013 election to replace former socialist leader Hugo Chavez.
Though the former bus driver's grip on power appeared shaky initially with a united opposition crying fraud and talk of splits within the ruling Socialist Party, Maduro has slowly consolidated his political standing since then.
But with no national elections due to be held until a parliamentary vote in 2015, Maduro's primary threat now appears to come not from Venezuela's opposition ranks, but from the country's deep-seated economic problems.
Venezuelans suffer the highest inflation in the Americas and endure frequent shortages of basic products. The capital, Caracas, has also become one of the world's most dangerous cities.
Venezuela and Cuba have been strong allies since Chavez came to power in 1999, leading a radical "anti-imperialist" group of Latin American and Caribbean nations.
Caracas ships around 100,000 barrels-per-day of subsidized oil, seen as crucial to the Cuban economy, while Havana repays that in part by sending thousands of doctors, sports instructors, military advisers and others to Venezuela.
Though the Cubans have bolstered the Venezuelan government's popular welfare programs, they have also become a focus of resentment for many Venezuelan opposition activists.
The tournament, which also features teams from Venezuela, Mexico, Dominican Republic and Puerto Rico, ends on Saturday. Villa Clara has lost its opening three games. (Additional reporting by Deisy Buitrago; editing by Daniel Wallis, G Crosse)