VATICAN CITY (AP) — Black smoke poured from the Sistine Chapel’s chimney yesterday evening, signaling that the cardinals sequestered inside for the first papal conclave of the new millennium failed to elect a new pope.

The black smoke emanating shortly after 8 p.m. meant the 115 voting cardinal “princes” of the church would retire for the night and return to the chapel this morning for more balloting in their search for a successor to Pope John Paul II.

If two morning ballots fail to produce a pope, the cardinals could hold two more votes this afternoon.

Some 40,000 people who packed St. Peter’s Square to stare at the stovepipe jutting from the chapel roof shouted, “It’s black! It’s black!” and snapped photos with their cell phones.

White smoke will tell the world that the church’s 265th pontiff has been chosen to succeed John Paul, who died April 2 at age 84.

The cardinals, from six continents and representing 52 countries, began their secret deliberations late in the afternoon after the ceremonial closing of the massive doors of the chapel, which is decorated with frescoes by Michelangelo and wired with electronic jamming devices to thwart eavesdropping.

The excitement built as darkness set in and pilgrims watched close-ups of the chimney on giant video screens in the square.

As the smoke began pouring from the chimney, shouts of “e bianco! e bianco!” — “It’s white! It’s white!” — rippled through the crowd. But the cries quickly gave way to sighs of disappointment as the smoke blackened.

“At first it seemed that we had a new pope, so I had a lot of emotions. But of course we didn’t really expect to have a pope on the first day,” said Alessia Di Caro, a 23-year-old university student.

There was initial confusion when a Vatican Radio commentator said, “It seems white,” as the first puffs emerged from the chimney. But as thick, darker smoke followed, the station proclaimed it black.

“It looks like the stove wasn’t working well at first,” an announcer joked a few minutes later.

Before shutting themselves inside, German Cardinal Joseph Ratzinger led his fellow cardinals in reading aloud an oath of secrecy. One by one, they then filed up to a Book of the Gospels, placed their right hands on it and pronounced a second oath to keep their sessions secret.

Ratzinger’s admonition read, in part: “In a particular way, we promise and swear to observe with the greatest fidelity and with all persons, clerical or lay, secrecy regarding everything that in any way relates to the election of the Roman Pontiff and regarding what occurs in the place of the election, directly or indirectly related to the results of the voting; we promise and swear not to break this secret in any way…”

Ratzinger — a powerful Vatican official often mentioned as a leading candidate for pope — began by reciting a prayer at the palace. The cardinals chanted the Litany of the Saints as they made the short walk to the chapel, led by altar servers carrying two long, lit white candles and a metal crucifix.

In a stately and colorful procession carried live on television, they walked past a pair of Swiss Guards in red plumed hats standing at attention at the entrance to the chapel and took two steps into the voting area, where special devices were installed beneath a false floor to block cell phone calls or bugs in an unprecedented effort to secure the proceedings.

Most of the cardinals were clad in crimson vestments and hats except for two Eastern Rite prelates — Lubomyr Husar of Ukraine and Ignace Moussa I Daoud of Syria — who wore black. Ratzinger entered the chapel last — an honor bestowed upon the dean of the College of Cardinals.

Before the procession, Ratzinger asked for prayers from the church that a pastor fit to lead all of Christ’s flock would be elected.

“May the Lord lead our steps on the path of truth, so that through the intercession of the blessed Virgin Mary, the Apostles St. Peter and St. Paul, and of all the saints, we may always do that which is pleasing to him,” he said in Latin.

With Michelangelo’s “Last Judgment” as a backdrop behind the altar, depicting a muscular Jesus amid masses of people ascending to heaven and falling to hell, the cardinals took their assigned places behind their name placards, with a copy of the conclave ritual on their desks.

They then placed their red, three-cornered square birettas on the tables, leaving only their crimson skullcaps on their heads.