Thailand's justice minister Chaikasem Nitisiri said the army had not consulted the cabinet on their decision to impose martial law, but appeared to play down the move, saying it was "only taking over security" and it would not affect the cabinet.
Protest leader Jatuporn Prompan said his group would accept the imposition of martial law, but "won't tolerate a coup or other non-constitutional means" to grab power.
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Fine start to the week for most but turning wet and windy from Wednesday.
Thousands of people have lined the banks of the Mersey to see Cunard's three flagship ocean liners sail down the river.
Claims that surgeons used an old saw found in a cupboard to amputate a patient's leg are being investigated.