Thai Army chief General Prayuth Chan-ocha arrives to give a news conference at the Army Club, May 20, 2014.

Thailand's army declared martial law nationwide on Tuesday to restore order after six months of street protests that have left the country without a proper functioning government, but denied that the surprise move amounted to a military coup.

Thai soldiers stand in front of the National Broadcasting Services of Thailand television station, May 20, 2014.

The army imposed martial law across Thailand amid a deepening political crisis that has seen six months of protests and claimed at least 28 lives.

The declaration did not constitute a coup and was made in response to deteriorating security, an army general said.

A Thai soldier walks in front of the National Broadcasting Services of Thailand television station, May 20, 2014.

A Thai soldier mans a machine gun in central Bangkok, May 20, 2014.

Thai soldiers take their positions in the middle of a main intersection in Bangkok's shopping district, May 20, 2014.

Passersby pose for a photo with Thai army soldiers standing guard on a city center, May 20, 2014.

Thai soldiers take their positions in the middle of a main intersection in Bangkok's shopping district, May 20, 2014.

A soldier sits beside a machine gun mounted on a military vehicle after the Thai army took their positions in central Bangkok, May 20, 2014.

A soldier looks at commuters beside a machine gun mounted on a military vehicle, May 20, 2014.

A soldier mans a military vehicle after Thai army took positions in central Bangkok, May 20, 2014.

Thai soldiers stand in front of the Army Club, May 20, 2014.

A Thai soldier stands in front of the Army Club, May 20, 2014.

A Thai soldier sleeps with his weapon after his unit was deployed near pro-government "red shirt" supporters encampment in suburbs of Bangkok, May 20, 2014.

A Thai army officer briefs soldiers standing guard outside the National Broadcasting Services of Thailand, May 20, 2014.

A Thai army soldier stands guard outside the National Broadcasting Services of Thailand, May 20, 2014.

Thai army soldiers stand guard outside the National Broadcasting Services of Thailand, May 20, 2014.

Thai army soldiers patrol the offices of the National Broadcasting Services of Thailand, May 20, 2014.

View of a gun mounted on a Thai army vehicle as soldiers stand guard on a busy city center street, May 20, 2014.

Thai army soldiers stand guard on a city center street, May 20, 2014.

Passersby photo Thai army soldiers standing guard on a city center, May 20, 2014.

Thai army soldiers stand guard on a city center street, May 20, 2014.

A Thai army soldier stands guard on a city center street, May 20, 2014.

A foreign tourist poses for a photo as Thai army soldiers stand guard, May 20, 2014.