An attack using explosives against anti-government protesters in Bangkok has wounded at least 28 people. The violence comes as judicial authorities probe the prime minister's connection to a controversial rice-pledging scheme that critics say has been plagued by corruption.
Friday's midday attack wounded protesters who were marching with movement leader Suthep Thaugsuban, and followed a series of bombings in recent days against the anti-government camp.
Earlier Friday pro-government 'red shirt' supporters attacked a protest site 20 kilometers from the city center.
Phil Robertson, deputy Asia director for New York-based Human Rights Watch, said without dialogue further violence can be expected. "There's a significant risk of escalating violence if there are not some sort of negotiations, discussions between the two sides and if both sides don't restrain those within their ranks who might be poised to provoke or institute violence," he stated.
Since the anti-government protests began in November at least eight people have died -- including two police officers -- and dozens injured from tear gas and clashes between protesters and police.
Since the "Bangkok Shutdown" marches began this week, sporadic violence mostly occurred late at night. Friday's incident is the first targeting daytime marches.
On Thursday, Thailand's National Anti-Corruption commission (NACC) announced it was launching a full inquiry in Yingluck's role and oversight in a multi-billion dollar rice pledging scheme. Two former cabinet members and several state officials are also under investigation.
The NACC said if Yingluck is found negligent she would be called on to step down from all official duties.
NACC spokesman, Vicha Mahakhun, said the inquiry into the Prime Minister lay in her responsibilities as head of the rice policy committee. "We started the inquiry into the caretaker Prime Minister's alleged role on the basis that she was the chairperson of the national rice policy committee that oversaw the rice pledging scheme and plus her rank of the head of the government that she must take care of the administration of every minister," said Mahakhun.
Vicha said case against Yingluck is of gross negligence under the penal code of Thailand and the inquiry is expected to take two to three months.
The investigation is one of several that could implicate members of the prime minister's party. Government agencies also are looking into past attempts to reform the constitution and a $70 billion infrastructure spending program.
But political scientist and former government spokesman, Panitan Wattanyagorn, said the independent agencies will be cautious in handling the cases due to the highly charged political atmosphere.
"The charges on corruption on various projects are critical for these independent agencies to handle carefully. They realize that on one hand these cases have sufficient ground to prosecute or proceed involving high ranking offices in the government or the cabinet -- they need to be very careful in looking into these charges because the charges are quite serious," said Wattanyagorn.
Yingluck's government has faced growing protests since presenting a broad amnesty bill last year seen to benefit her older brother, Thaksin Shinawatra, who lives in exile to avoid a jail term for corruption. Under the terms of the bill, later voted down by the Senate, the amnesty would have also extended to cover members of Ms Yingluck's administration.
Yingluck, in a bid to ease political tensions, called early general elections for Feb. 2. But anti-government protestors are seeking her resignation and the appointment of a non-elected council to institute reforms.
The Prime Minister has remained adamant that the election will go forward as planned, despite the opposition Democrat Party's boycotting the vote.