Thai authorities gave confusing statements about the Bangkok bombing investigation Thursday, 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.”

Three days after the attack at a revered shrine in central Bangkok killed 20 people, authorities appeared to have few solid leads into the perpetrators of the deadliest attack in Thailand’s recent history. Police said they suspect the plot involved at least 10 people but described that figure as theoretical.

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. Police on Wednesday issued an arrest warrant describing the suspect as a tall “foreign man” with a fair complexion, a prominent nose and thick lips.

In a televised statement Thursday, however, military spokesman Col. Winthai Suvaree 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.

When contacted by telephone for clarification, he said that a link to global terrorism hadn’t been ruled out. “We still have to investigate in more detail,” he said.

Winthai also said on television that Chinese tourists, who were among the victims, were not the “direct target.”

The Monday evening attack at the Erawan Shrine, a popular tourist site that is known to attract Chinese visitors, left 20 people dead and more than 120 injured. Four Chinese citizens were among the dead.

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. Though there has been little violence aimed at Thailand’s coup, whose leaders have cracked down on dissent, the “Red Shirt” movement that supported the ousted elected government clashed with the military in 2010 protests that left about 90 people dead. There could even be infighting within the army ahead of an annual military reshuffle.

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.

Police officials told reporters Thursday that authorities believed those behind the blast 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.

“This was a network. We think they would have needed at least 10 people,” said national police spokesman Lt. Gen. Prawut Thavornsiri.

The comments appeared to be speculative, not based on firm evidence. National police chief Somyot Poompanmoung said later Thursday, “I didn’t say there are 10 suspects. I said theoretically they need more than 10 people.”

Police released a sketch of the suspect seen on video leaving the backpack: a young man wearing glasses with black-bushy hair.

Police on Thursday doubled the reward for clues leading to the suspect’s arrest to 2 million baht, or $56,000, Somyot said. He told reporters that a Thai businessman who wished to remain anonymous had added to the 1 million baht reward police set a day earlier.

A motorcycle taxi driver believed to have driven the suspect away from the scene told police the suspect handed him a piece of paper saying “Lumpini Park,” a nearby park, and was talking on the phone in a foreign language that was not English, Prawuth said. Police don’t know what language it was.

Bangkok police on Thursday said they were trying to locate a tuk-tuk driver who may have driven the same suspect to the Erawan Shrine, and announced a 30,000 baht ($850) reward for him to come forward.

Among the 20 people killed, Thai authorities have identified six victims as Thai and four as Malaysians, along with four Chinese, two people from Hong Kong including a British citizen, one Indonesian and one Singaporean. Two victims remain unidentified.

Two other people seen on the video near the man with the backpack are also considered suspects in Monday’s deadly bombing, police said late Wednesday.

Story from The Associated Press.

Thai police, military rulers show little progress in Bangkok bombing investigation

Thai police have cleared two suspects. Otherwise little progress is being reported in finding a man in surveillance video. Authorities believe he set off explosives that killed 20 people. CCTV’s Tony Cheng filed this report on how many people are questioning the Thai security services.

Follow Tony Cheng on Twitter @TLCBkk

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