JAKARTA, Indonesia, Wednesday, Aug. 6 — A sport utility vehicle packed with explosives blew up here in Indonesia's capital early Tuesday afternoon, killing at least 10, and as many as 15, people and wounding nearly 150 in a Marriott hotel, a large restaurant and an office building. It was the most devastating attack on Indonesian soil since the twin blasts in Bali last October.

There were no immediate claims of responsibility, but because all three buildings were frequented by Americans, Indonesia's vice president, Hamzah Haz, said the attack appeared to have been aimed at American interests.

But the toll may be high among Indonesians. An American Embassy spokesman said here today that no Americans had been killed, though one had been treated for injuries and released and a second was still being treated at a local hospital but was not in critical condition. Local news media said this morning that of 15 dead counted at various hospitals, all but one was Indonesian.

PT Rabobank Duta Indonesia, a bank that is majority-owned by Rabobank of the Netherlands, said the blast had killed Hans Winkelmolen, a Dutch citizen who had been its president until last Friday.

Indonesia is the world's most populous Muslim nation. The faith has traditionally been moderate here, but more radical pockets have taken root in recent years, first bringing separatist fighting, then terrorist attacks. Many have been linked to the group Jemaah Islamiyah, which has itself been linked to Al Qaeda.

The explosion on Tuesday came two days before an Indonesian court was expected to announce a verdict in the first of a number of cases of men suspected to be members of Jemaah Islamiyah and accused of planning and carrying out the Bali attack, which killed 202 people, many of them Australian. At least one suspect has said the Bali attacks were meant to hurt "America and its allies because they are international terrorists."

The White House strongly condemned the bombing Tuesday and said it would provide any assistance possible to Indonesia.

Prime Minister John Howard told the Australian Broadcasting Corporation that the attack "had all the hallmarks of Jemaah Islamiyah."

The Jakarta government immediately said it would impose more stringent controls on its people. Susilo Bambang Yudhoyono, the coordinating minister for political and security affairs, said after a cabinet meeting, "Those who criticize about human rights being breached must understand that all the bombing victims are more important than any human rights issue."

The explosion on Tuesday appeared to have been carefully planned and timed. Indonesian officials said the vehicle was apparently moving through the horseshoe-shaped driveway serving the buildings when it exploded, and they suggested that this pointed to a suicide bomber. The police said the vehicle was a Toyota Kijang, which can carry eight people in its three rows of seats. (It is slightly larger than the Toyota 4Runner sold in the United States.) The S.U.V. burned fiercely after the blast.

The explosion took place at lunchtime, devastating the hotel's Sailandra Restaurant, a popular gathering place for expatriates and wealthy Indonesians. It ripped a six-foot hole in the pavement, tearing open a ragged skylight for the hotel basement below.

It seriously damaged the 33-floor Marriott's lower floors and blew in windows on its higher floors. John Wolf, a Marriott spokesman, said 273 guests were registered. Three guests and eight hotel employees were injured, he said. He added that while no Marriott employees had been killed, he did not know whether any guests were among the dead.

The hotel, which opened just two years ago, had been a symbol of Indonesia's gradual recovery from the Asian financial crisis of 1997, which so devastated the economy that it remains under the supervision of the International Monetary Fund. The bombing is a serious blow to hopes of emerging from that supervision by the end of this year. The American Embassy held its last two July 4th parties at the hotel.

The office building, which houses the offices of many American companies, was also damaged.

This morning, more than 100 local residents watched silently, pointing at some of the worst gashes in the buildings' facades, while four long military trucks stood near the Marriott. Dozens of white-shirted police officers stood outside the yellow tape cordoning off the site. Investigators appeared slow to enter the site, perhaps because of the criticism Indonesia received after evidence was not preserved at the Bali scene.

Six incinerated taxis still stood near the entrance to the driveway while two gray, soot-stained pieces of metal that appeared to be chunks of automotive body panels could be seen in the Marriott's blue-tiled swimming pool, located on a terrace 20 yards above street level and nearly 100 yards from the site of the blast. In an adjacent office building, workers on several floors were picking up glass that had gone scything across offices shortly before 1 o'clock on Tuesday afternoon.

President Megawati Sukarnoputri visited the site within hours, but made no public statement.

The first verdict in the Bali cases, involving the trial of Amrozi, a defendant who is accused of playing a central role in planning that attack, is to be handed down on Thursday.

Abu Bakar Bashir, a 64-year-old cleric whom intelligence officials have described as leading Jemaah Islamiyah, is being tried separately for subversion, although he is not accused of direct involvement in the Bali attacks; he has denied that Jemaah Islamiyah exists.

The man believed to be Jemaah Islamiyah's top bombmaking expert, Fathur Rohman al-Ghozi, escaped from a jail in the Philippines last month. Another activist often described as the former operations chief of Jemaah Islamiyah, Riduan Isamuddin, also known as Hambali, has been the target of an international manhunt by law enforcement agencies since 2001. He is believed to be the link between Al Qaeda and the Indonesian group.

Noel Choong, the southeast Asian regional manager of the International Maritime Bureau Piracy Reporting Center, said in an interview last week in Kuala Lumpur, Malaysia, that Jemaah Islamiyah was an especially hard group to counter because its very loose organization meant that even a handful of activists could decide to carry out an attack.

Indonesia has considerable oil and natural gas reserves and lies astride the main routes used by ships carrying oil from the Mideast to East Asian countries. It has been struggling to rebuild its tourism industry since the Bali bombings.

The State Department renewed on June 12 its advice for Americans to defer all nonessential travel to Indonesia, citing the continued risk of terrorism as well as a stepped-up effort by the Indonesian military since May to suppress a secessionist movement in Aceh province, in the country's northwestern corner.