Ruth Fernandez, a pioneer Puerto Rican singer who broke racial and gender barriers and was later elected a senator for the U.S. territory, has died. She was 92.

Fernandez died late Monday of septic shock and pneumonia, producer Vicky Hernandez told reporters.

Many Puerto Ricans on Tuesday mourned the passing of the woman with a deep voice known as the "soul of Puerto Rican song." The government declared three days of official mourning with Puerto Rican and U.S. flags flown at half staff.

"A true glory of Puerto Rico has died," former Gov. Rafael Hernandez Colon said. "Ruth Fernandez was a pioneer in several artistic fields, and she blazed a trail so that other Puerto Rican artists could gain prominence on the island and project themselves at an international level."

"Arriba, corazones!" ("Lift up your hearts!") was the trademark exhortation of Fernandez, who was the first woman singer to perform in a Puerto Rican orchestra.

She also broke barriers off the Caribbean island, performing as the first popular music interpreter booked by the Metropolitan Opera House in New York, according to Puerto Rico's nonprofit National Foundation for Popular Culture.

Born May 23, 1919, in Ponce, Puerto Rico's second largest city, Fernandez began singing professionally at age 14.

By age 16, she was hired as the main singer by Mingo and the Whoopee Kids, among the more popular local bands at the time, the foundation said.

During a concert at the Vanderbilt Hotel in the capital of San Juan, Fernandez was asked to enter the stage through the kitchen because she was black. She refused and entered through the hotel's front door.

Fernandez sang in shows around the world, including a concert at New York's Carnegie Hall.

She later represented her hometown of Ponce in the Puerto Rican senate in 1973-1980 as a member of the Popular Democratic Party.

Rossana Lopez Leon, who previously oversaw the Puerto Rican government's agency for the elderly, described Fernandez as a woman ahead of her time who broke through racial and gender barriers.

Married twice, but with no children, Fernandez was nevertheless known as "Aunt Ruth" to many.

"I know the people of Puerto Rico mourn this loss," Gov. Luis Fortuno said. "We will remember her by her powerful voice and strong personality."