DENVER (AP) _ The pope's U.S. representative on Friday celebrated a Mass of Christian Burial for James V. Casey, archbishop of the Denver Catholic Archdiocese, before a capacity crowd at the Basilica of the Immaculate Conception.

Casey, 71, died last Friday following a two-week illness caused by hemorrhaging in the brain. He had served the archdiocese's 310,000 Catholics in Denver and northern Colorado since 1967.

The service was celebrated by Archbishop Pio Laghi, apostolic pro-nuncio in the United States. It ended three days of public mourning for Casey.

About 50 bishops, archbishops and cardinals attended the Mass.

''He (the pope) wanted me to be here today to tell you of his sadness over the archbishop's death,'' Laghi told mourners.

Shortly after his arrival in Denver, Casey established a reputation as a social activist. In 1968, he announced a three-year, $1 million pledge to help the poor of the archdiocese. In July 1970, he became the second Catholic bishop to issue a Vietnam War peace message.

Recently, he led a campaign to build a shelter for Denver's homeless that currently is under construction.

The pope is expected to name Casey's replacement in about three months.

The Rev. Lawrence St. Peter, 56, the archdiocese's vicar for priests, was named temporary administrator of the archdiocese.