She also demanded the arrest of others, including immediate family members of Chief Minister M Karunanidhi, allegedly involved in the scam and said her party will not give up its demand for a Joint Parliamentary Committee probe into the scam despite Raja`s arrest.
Asked whether the arrest had something to do with Congress and DMK firming up their alliance with the visit of Karunanidhi to Delhi two days ago, she said the whole thing looked "very artificial and deeply suspicious".
She believed that the decision to arrest Raja was taken keeping in mind the Assembly elections in Tamil Nadu. It was a "purely political" decision, she said.
"Raja`s arrest raises more questions than it answers and many questions have been left unanswered. This arrest can be described only as an action too little, too late," she said.
Alleging that the action came three years late, she said, "The government would have arrested him three years ago, at least two years, one year or even when the Supreme Court asked why Raja was not arrested."
She said the government was contradicting itself as its different arms were giving contradictory statements. "The government has contradicted itself. CAG says the allocation has led to enormous loss to the tune of Rs 1.76 lakh crore.
"But, Telecom Minister Kapil Sibal, whom I presume spoke on behalf of the government, claims that Raja did not cause any loss to the exchequer and even came up with an argument of zero loss. But then why did CBI, another arm of the government, arrest him. If Raja had done nothing wrong, why has he been arrested?" the AIADMK leader posed.