Henryk Gorecki, a renowned Polish composer whose early avant-garde style gave way to more approachable works rooted in his country’s folk songs and sacred music and whose Symphony No. 3 — an extended lamentation subtitled “Symphony of Sorrowful Songs” — sold more than 1 million copies on CD in the 1990s, died Friday in Katowice, Poland. He was 76.

Joanna Wnuk-Nazarowa, the general director of the Polish National Radio Symphony Orchestra in Katowice, announced Gorecki’s death, telling The Associated Press that he had been hospitalized with a lung infection. Gorecki lived in Katowice.

Gorecki, who with Witold Lutoslawski and Kzysztof Penderecki was one of Poland’s most revered contemporary composers, wrote music that often played with the extremes of musical expression. In works like “Old Polish Music” (1969), blocks of assertive, high-energy brass writing are juxtaposed with eerie, slow-moving, pianissimo string passages.

His intensely focused “Beatus Vir” (1979) and “Totus Tuus” (1987), both dedicated to Pope John Paul II, draw on the simplicity of traditional chant as well as richly harmonized, intensely focused choral writing and, in the case of “Beatus Vir,” monumental orchestral scoring. And in “Already It Is Dusk” (1988), his first string quartet, Gorecki reconfigures Polish dances and dirges, casting the more outgoing sections in acidic harmonies that give the score a searing, angry edge.

But the work for which Gorecki is most widely known, Symphony No. 3 (1976), explores the gradations of a single mood: somber, introspective reflection, conveyed in three long, slow, quiet movements that last nearly an hour.

Scored for orchestra and soprano, the work’s vocal sections include settings of a 15th-century sacred lamentation, a simple prayer (“Oh Mamma do not cry — Immaculate Queen of Heaven support me always”) scrawled by a young girl on the wall of a Gestapo prison in southern Poland, and a plaintive Polish folk song in which a mother grieves for a son lost in war.

Gorecki surrounds these texts with a compelling amalgam of lush neo-Romanticism; open, entirely consonant tonality; and a gradual unfolding of themes and textures that struck many listeners as a distinctly Eastern European approach to Minimalism.

The work quickly took on a life of its own. In 1985, French director Maurice Pialat used an excerpt from the symphony on the soundtrack to “Police,” a film starring Gerard Depardieu. A recording of the full work, conducted by Ernest Bour, with soprano Stefania Woytowicz, was released on the Erato label, and although it was packaged as a soundtrack album for “Police” — a film virtually unknown in the United States — it proved a first encounter with Gorecki’s music for many American listeners. Two more recordings were released, both with Woytowicz as the soloist.

But the work did not achieve its explosive success — a surprise, given its unceasingly mournful character — until a recording by the soprano Dawn Upshaw, with David Zinman conducting the London Sinfonietta, was released on the Nonesuch label in 1992. The recording became a radio hit in Britain, where it broke into the Top 10 on the Music Week pop chart, and sold more than a million copies worldwide. For a while, Nonesuch said, it was selling 10,000 copies a day in the United States.

The symphony was subsequently used as soundtrack music in Peter Weir’s “Fearless” (1993) and Julian Schnabel’s “Basquiat” (1996). Samples of the score were also used in recordings by several pop groups, most notably “Gorecki” by the English band Lamb.

Henryk Mikolaj Gorecki was born in the village of Czernica on Dec. 6, 1933, to parents who were amateur musicians. He began studying the violin when he was 10, and later took up the clarinet and piano. By the early 1950s, he was composing songs and piano works while earning a living as a teacher. In 1955, he enrolled at the Music Academy in Katowice, where he spent the next five years as a composition student of Boleslaw Szabelski.

But he was already beginning to make his name in Polish avant-garde circles with works like the Four Preludes (1955) for piano and the contrast-rich Sonata for Two Violins (1957).

In “Epitafium” (1958), for mixed choir and instruments, he began experimenting with the spatial placement of his performing forces. In the Symphony No. 1 (1959) and “Scontri” (“Collisions,” 1960), he experimented with Serialism (in which a composer must use all 12 tones of the chromatic scale in equal proportion) and with the textural contrasts — dense clusters versus spare, pointillistic solo lines — that would become a hallmark in his later music.

Gorecki received honorary doctorates from the University of Warsaw, the Music Academy in Krakow and Concordia University in Quebec, and an honorary fellowship from Cardiff University. Last month Bronislaw Komorowski, the president of Poland, visited Gorecki in the hospital to award him the country’s highest honor, the Order of the White Eagle.