* Unknown explosive thrown at anti-government protesters
* Govt wants to take back part of blockaded admin complex
* PM says she has overwhelming public support (Adds context, stock market reaction to blast)
By Amy Sawitta Lefevre
BANGKOK, Jan 17 (Reuters) - An explosive device tossed at anti-government protesters wounded 36 in central Bangkok on Friday and other violence rippled through the Thai capital after several days of relative calm when the movement appeared to be running out of steam.
At least one protester was seriously hurt.
Police said the device was hurled at protesters marching with their leader, Suthep Thaugsuban, near Chulalongkorn University in the city centre.
"When the incident happened and perpetrators threw the explosive, Suthep was 30 metres away," Akanat Promphan, a spokesman for the movement, told Reuters. Suthep was unharmed.
It was not immediately clear who was responsible and the nature of the device was unknown as forensic experts were prevented from entering the area.
"We have received 12 people who were injured in the blast. One person is seriously injured and the other 11 have sustained various types of injuries, some minor," said an official at Ramathibodi Hospital.
The overall injury toll came from the Erawan Medical Center, which monitors Bangkok hospitals.
The latest unrest flared in November and escalated on Monday when the demonstrators led by Suthep, a former opposition politician, brought parts of the capital to a standstill and forced many ministries to close.
They accuse Prime Minister Yingluck Shinawatra and her brother, former premier Thaksin Shinawatra, of corruption and say they want her to step down to make way for an unelected "people's council" to push through broad political reforms.
She has called an election for Feb. 2 and now heads a caretaker administration, but the protesters and opposition parties are boycotting the vote and want her to go immediately.
The protests have been relatively peaceful until now, but sporadic flare-ups between protesters, police and government supporters have left eight people dead and scores injured.
The demonstrations are the biggest since pro-Thaksin protesters paralysed Bangkok in April-May 2010. That movement ended with a military crackdown and more than 90 people, mostly protesters, were killed during the events.
The stock market fell on Friday as investors cut some risk exposure after the blast and was down 0.5 percent at the end of trading. The baht currency also fell but was a shade higher on the day.
TAKING BACK CONTROL?
Foreign Minister Surapong Tovichakchaikul earlier said it was "about time" to take back control of Bangkok and that a delegation of officials, escorted by police and troops, would make a start by going to a government office that issues passports to try to persuade the protesters to let work resume.
"If successful, this can be an example for other ministries to follow," Surapong told a news conference.
Asked if the government was now moving to end the blockade of ministries and key intersections, he said: "Soon. It's about time. We have to start to do something."
In the event, the delegation never made it.
"We talked to the protest leaders on the phone and our security adviser, given the explosion earlier, advised us not to go," said Sek Wannamethee, a Foreign Ministry spokesman.
Earlier, hundreds of people on motorbikes and in other vehicles drove up to the government area where the passport office is located and a confrontation ensued with the protesters, National Security Council Secretary-General Paradorn Pattanatabut told Reuters.
"They said they were angry at the anti-government crowd who blocked traffic there and stopped them from getting access to government services, especially the passport office," he said.
The turmoil is the latest episode in an eight-year conflict pitting Bangkok's middle class and royalist establishment against poorer, mainly rural supporters of Yingluck and Thaksin.
That support has enabled him or his allies to win all elections since 2001 and Yingluck's Puea Thai Party seems certain to win the upcoming vote.
The government says it must be held on Feb. 2 as parliament has been dissolved and the date endorsed by the king.
Reuters reporters said at least 2,000 protesters in pickup trucks and vans headed towards a printing works north of the central Bangkok, saying it was producing ballot papers and claiming it would be printing far more than were needed.
Speakers at protest sites across central Bangkok have suggested that Yingluck is worn out and eager to quit, but at a news conference on Friday, the prime minister maintained she still enjoyed overwhelming popular support.
As the deadlock between the government and protesters drags on, many Thais believe the military could step in to break the impasse, especially if the protests turn more violent.
The army has staged or attempted 18 coups in 81 years of on-off democracy but has tried to remain neutral this time.
The security forces have largely kept out of sight since the blockades began this week, with the government reiterating on Friday it was keen to avoid any confrontation. (Editing by Alan Raybould, Nick Macfie and Ron Popeski)