2nd Update
Director General of the Media Centre for National Security Lakshman Hullugala told state television a short while ago that General Sarath Fonseka who was arrested late this evening will be Court Marshalled for the military crimes he has committed. 

The government has accused General Fonseka of plotting to assassinate the President and overthrow the government by a coup and reveling military secrets. The government has arrested over 50 of his loyal retired military officers on planning the coup. General Fonseka denies all government's accusations against him.

Gen Fonseka's wife has confirmed to BBC that her husband had been detained after stepped up the security presence around his office in Colombo.

It is reported that Gen Fonseka was having a meeting with number of politicians who had supported his candidacy.
Muslim Congress leader Rauff Hakeem told the media “The Genaral was dragged away in a very disgraceful manner in front of our own eyes.That action was authoritarian and vindictive".

JVP spokesman told Agency France-Presse: "The general refused to be taken away. They grabbed him and virtually carried him away after threatening the others. There must have been over 100 soldiers."

The politicians at the meeting said the military police had given no reasons as they made the arrest.
Mr Hakeem told Theo media Gen Fonseka had complained that because he was no longer in the military he should not have been arrested by military police.
 

1st Update

Opposition Presidential candidate and former army Chief Gen. Sarath Fonseka along with his media secretary Senaka de Silva has been arrested by Sri Lankan military police a short while ago. This was reveled to the media by parliamentary member of the opposition Mano Ganeshan.

New appointed military spokesman Major Prasad Samarasingha has also confirmed that the General has been arrested in his office in Colombo.

Speaking to journalists in Colombo today, Gen. Fonseka told "I am not going to save anyone who has committed war crimes. I am definitely going to reveal what I know, what I was told and what I heard. Any one who has committed war crimes should definitely be brought into courts," Gen. Fonseka said.

"Those who reveal the truth are not traitors" he added.

During the last presidential election Gen. Fonseka challenged president Mahinda Rajapaksa. Fonseka first accused Defence Secretary of giving unlawful orders to Maj. Gen. Savinrda Silva to shoot top LTTE leaders coming with white flags to surrender. Then one day later he withdrew the statement denying it, saying he was misquoted.

US state department, Int. Human Rights Organisations has alleged Sri Lankan government and forces committing  war crimes during the final phase of the war against Tamil Tigers and have demanded an investigation as well as to try the Sri Lankan state in international courts on alleged abuses against civilians and surrenders.

Few days back Defence Secretary told the BBC that he will not allow anyone to carry out any investigation against Sri Lanka on War crimes.