Police said Thursday that they were looking for an alleged architect of the 2002 Bali attacks as a possible engineer of the suicide bombings that killed 19 people in addition to the bombers on the island Saturday.

The suspect, Zulkarnaen, who like many Indonesians uses only one name, is considered to be far more senior and skillful than the first two suspects, Noordin Mohammed Top and Azahari Husin, police and intelligence analysts said. Noordin and Azahari, both Malaysians, are also wanted in the 2002 attacks, and all three men are members of the Indonesian militant group Jemaah Islamiah.

Zulkarnaen, a member of Jemaah Islamiah's central committee, trained in Pakistan in the mid-1980s and created the group's special operations unit. He is "widely considered to be potentially the most dangerous at large because of his knowledge and influence," said Ken Conboy, a security analyst who has recently written a book, "Second Front," about Jemaah Islamiah.

Yet Zulkarnaen, a slightly built man who is about 45 years old, has rarely been photographed, seen or heard in public. "He's a very cunning character," Conboy said.

If police determine that Zulkarnaen was involved in the attack Saturday along with Noordin and Azahari, it would mean that three of the most dangerous Jemaah Islamiah members had continued to collaborate after the 2002 attack and that the network's most militant faction "might be stronger than we thought," said Sidney Jones, Southeast Asia project director for the International Crisis Group and an expert on militant organizations.

Noordin and Azahari, who are also accused of helping organize suicide bombings in Jakarta in 2003 and 2004, have narrowly eluded police at least six times. Just four months ago, Noordin escaped arrest by dressing in a burqa, a traditional woman's covering, said Abdul Madjid, the police chief in Solo, a town in central Java that has produced Jemaah Islamiah operatives.

Three days before the blasts Saturday, police said, Zulkarnaen's wife called a cell phone number in Bali from Solo. The number belongs to a fugitive on a terrorism watch list, according to Madjid, who would not identify the person by name.

The wife, Rayahuningtyas, called the number several times from a pay phone on the grounds of an Islamic boarding school where she lives, Madjid said. The school was co-founded by the spiritual head of Jemaah Islamiah, Abubakar Baasyir, who is in prison for conspiracy linked to the 2002 Bali bombings. Zulkarnaen graduated from the school in 1981.

The nationwide hunt for the plotters of the bombings, which killed 19 people and three suicide attackers at three popular restaurants, involves hundreds of thousands of police on Bali, Java and elsewhere.

President Susilo Bambang Yudhoyono is also planning to enlist the military in the fight against terrorism. On Wednesday, he called for the revival of a domestic security function for the military. The police have had the primary role in this area since the reform era of the late 1990s. Civil liberties groups have concerns that the military's reentry into internal security could revive opportunities for abuses of power that were rampant under the authoritarian government of President Suharto.

Meanwhile, police have televised pictures of the three suicide bombers, whose nearly intact heads were recovered from the blast sites. As a result, an informant identified one as Gareng, whose name police found on the terrorism watch list, Madjid said. "We are still unsure whether he is the one," he cautioned. "We are doing further investigation."

Gareng was last seen in June 2004 in Solo, Madjid said. He lived in downtown Solo in the Red Zone, an area known to be frequented by militants, which includes the school Baasyir founded, Madjid said. Gareng is best known as a clothing vendor.

Not all of the tips have been good. The family of one man, whom they had not seen in two years, suggested that he was one of the suicide bombers. The man appeared on television Wednesday night to deny the allegation.

In addition to the photos and a hotline, police are using unorthodox methods to solve the case. On Sunday, a young woman went into a trance on Jimbaran Beach near the site of one of the bombings, shouting out names and addresses of places she said should be checked for the bomb plotters. The police investigated but turned up nothing. "We have to follow all leads," the island's police chief, I Made Pastika, said Thursday.

Special correspondent Yayu Yuniar contributed to this report.

Indonesian police cordon off one part of an area they reopened to the public Thursday, five days after suicide bomb attacks at three restaurants in Bali.Two girls watch as police open the public part of a road near the site of the recent attacks, which killed 22 people, including the bombers.