BANGKOK – Somber horns sounded Friday at the site of Bangkok's deadly bomb blast as officials joined a multi-religious ceremony for victims of this week's attack, the latest effort to show that the bustling capital was respectfully, if cautiously, moving on.
Four days after the explosion at the revered Erawan Shrine, at one of the capital's busiest intersections, there were few solid leads into the perpetrators of the deadliest attack in Thailand's recent history. Police were still searching for the prime suspect seen in a security video, a day after clearing two other men initially believed to be suspects.
On Friday, after being criticized for sending confusion messages, authorities were more guarded in their statements.
"The Royal Thai Police have reported that much progress has been made. However, the details cannot be disclosed at this time," Col. Winthai Suvaree said in a televised statement. He added that security was stepped up at tourist sites and security agencies had determined "this was an act aimed to cause extensive damage to the economy, and tourist industries as well as the nation's image."
In a sign of the concern over more attacks, bomb-sniffing dogs checked the shrine ahead of Friday's morning ceremony, where government officials and diplomats laid floral bouquets. A Brahmin priest poured holy water over the damaged face of the shrine's centerpiece, a four-headed statue of the Hindu god Brahma that is now missing one chin.
But other signs of the blast have been quickly removed: Overnight, workers soldered new iron railings to replace those twisted by Monday night's explosion. The crater left by the blast has been paved over with fresh cement.
After the Hindu ceremony at the shrine, officials held rites for the victims in a multi-religious prayer ceremony attended by Buddhist, Christian, Hindu, Sikh and Muslim priests and representatives.
Office worker Pratuang Limkul was among many Bangkok residents who also came to pay respects.
"I came to send the spirits of those in this place to rest in peace," she said, after kneeling in prayer.
Among the 20 people killed, Thai authorities have identified six victims as Thai and four as Malaysians, along with four mainland Chinese, two people from Hong Kong including a British citizen, one Indonesian and one Singaporean. Two victims remain unidentified. More than 120 people were injured by the explosion.
The attack has raised concerns about safety in a city that draws millions of tourists, but life has returned to normal quickly. Subways and shopping malls were bustling and aside from bag inspections at stores and hotel entrances, there was little visible extra security. Authorities say security has been tightened citywide mainly with plain clothed officers.
Authorities made confusing statements Thursday about the investigation, with a military spokesman saying they believe the attack wasn't the work of international terrorists — a day after police issued an arrest warrant for the prime suspect that described him as a "foreign man."
So far the firmest clue comes from security camera footage that shows a young man in a yellow T-shirt leaving a backpack at the crowded shrine. Time stamps on the video show he left the temple about 15 minutes before the explosion.
Two other people seen on the video near the man with the backpack were initially considered suspects but cleared Thursday after one of them turned himself in and said he was a tour guide and the other was a Chinese tourist, said national police spokesman Lt. Gen. Prawut Thavornsiri.
Police have released a sketch of the man with the backpack — depicting him as a young man with eyeglasses and bushy, black hair — and offered a 2 million baht ($56,000) reward for clues leading to his arrest. A warrant issued Wednesday describes him as a "foreign man."
But on Thursday, Winthai, the military spokesman, cast doubt on an international connection.
"Security agencies have collaborated with intelligence agencies from allied countries and have come to the same preliminary conclusion that the incident is unlikely to be linked to international terrorism," Winthai said in a televised statement. He added that Chinese tourists were not the "direct target."
Separately, national police chief Somyot Poompanmoung said Thursday police suspect the plot involved at least 10 people but described that figure as speculative.
"I didn't say there are 10 suspects. I said theoretically they need more than 10 people," he said.
The speculation was based on the nature of the attack, Somyot said, which must have planned it in advance, maybe a month ahead of time, and would have needed a site inspection team, bomb makers, bombers and an escape team.
No one has claimed responsibility for the blast, sparking a variety of theories into who might be behind it. One is that the blast was a revenge attack related to Thailand's recent deportation to China of more than 100 Uighur Muslims, or that it could have been carried out by Islamist groups expanding their reach in Southeast Asia.
Other speculation points closer to home. Muslim separatists have been waging a low-level but deadly insurgency in southern Thailand since 2004, leaving more than 5,000 people dead, but virtually all their attacks have been confined to the southernmost provinces.
There has been little violence aimed at Thailand's coup. Political violence boiled over during 2010 protests, when the "Red Shirt" movement that supported the ousted elected government clashed with the military, leaving about 90 people dead.
Associated Press journalists Grant Peck, Tassanee Vejpongsa and Penny Yi Wang contributed to this report.