A host of celebrations in honor of recently freed Puerto Rican nationalist Oscar López Rivera has outraged the families of those who lost relatives in a string of bombings during 1970s and 80s linked to his group, even as many Puerto Ricans hail him as a patriot and political prisoner.

Lopez, whose 55-year prison sentence was commuted by President Barack Obama, was free from house arrest in San Juan earlier this week and is expected to be on hand Thursday for a celebration in his honor in the Chicago neighborhood of Humboldt Park. Numerous politicians and supporters are expected to be on hand for the march, including Rep. Luis Gutierrez, D-Illinois, and Billy Ocasio from the National Puerto Rican Museum of Art.

“Oscar is a patriot and a hero to Puerto Ricans all over the world and his return to Chicago is an event I have spent my entire career working towards,” Gutierrez said in a statement provided to Fox News. “I cannot begin to say how proud I am and how overjoyed my wife and my daughters are to welcome Oscar to Chicago and that we will be able to walk the streets of Chicago with Oscar as a free man.”

El nacionalista puertorriqueño Oscar López Rivera saluda tras salir en libertad después de estar confinado a arresto domiciliario en San Juan el 17 de mayo del 2017. (AP Photo/Carlos Giusti) (AP Photo/Carlos Giusti)

López was considered a top leader of the Armed Forces of National Liberation, or FALN, an ultranationalist Puerto Rican group that claimed responsibility for more than 100 bombings at government buildings, department stores, banks and restaurants in New York, Chicago, Washington and Puerto Rico during the 1970s and early 1980s. The FBI classified the Marxist-Leninist group as a terrorist organization.

The most famous bombing was the still-unsolved 1975 explosion that killed four people and wounded 60 at Fraunces Tavern, a landmark restaurant in New York's financial district.

López, a Vietnam War veteran who moved from Puerto Rico to Chicago as a child, wasn't convicted of any role in the bombings that killed six people and injured scores, but those who lost loved ones hold him responsible.

“Oscar López Rivera is a convicted terrorist. Bottom line,” Joseph Connor, whose father, Frank, was one of the people killed in the Fraunces Tavern bombing, told Fox News. “Maybe he didn’t actually plant the bomb, but he was the leader of the FALN in the same way that Usama bin Laden was with Al Qaeda.”

Along with the celebration in Chicago, supporters also plan to honor López at the National Puerto Rican Day Parade along New York's Fifth Avenue in June. There were numerous reports that Goya Foods – a sponsor of the parade since it began 59 years ago – had retracted its sponsorship over the decision to honor López, but a spokesperson the company told Fox News that the move was “a business decision.”

“It was a business decision not to participate in the parade,” Rafael Toro, the director of public relations at Goya, told Fox News. “There was a false letter sent out by someone that we do not know, but it was not released by Goya.”

Oscar López Rivera is a convicted terrorist. Bottom line.
— Joseph Connor, son of victim of Fraunces Tavern bombing

López, now 74, was sentenced to 55 years in prison in 1981 after he was found guilty of seditious conspiracy, armed robbery, a weapons violation and four counts of interstate transportation of stolen vehicles. A federal judge termed him an "unreconstructed revolutionary" and López said Puerto Ricans should fight for their island's independence "by any means necessary."

He later faced an additional 15 years in jail after he was convicted of conspiring to escape from prison in Leavenworth, Kansas.

In 1999, President Bill Clinton offered López clemency but the inmate rejected the offer because it excluded two associates who have since been released. Then in 2011, the U.S. Parole Commission denied his request for an early release.

Obama commuted his sentence in his final days in office, along with giving clemency for others, including Chelsea Manning, the transgender Army intelligence analyst who leaked more than 700,000 U.S. documents.

While maligned by the families of bombing victims, López during his time behind bars became a cause célèbre among many progressive politicians and celebrities, including Vermont Sen. Bernie Sander and “Hamilton” creator Lin-Manuel Miranda.

The Associated Press contributed to this report.