According to police, Salu was picked up from her home at Changanassery near Kottayam and taken to nearby Chengannur for questioning by the special investigation team headed by ADGP Hemachandran.
The scam, pertaining to fraudulent deals running into huge sums pushed by Saritha Nair and accomplice Biju, has brought the office of Chief Minister Oommen Chandy under a cloud with the arrest of one of his close personal aides and removal of two others from his staff.
She had been under scanner right from the start and the investigators came across evidences that pointed that she had helped Biju escape from the state, sources said.
Biju, also wanted in connection with the death of his wife in suspicious circumstances besides being the co-accused in the solar cheating case along with Saritha, was arrested from Coimbatore a few days back.
The opposition LDF had also been pressing for her arrest after it was found that several top politicians, including Home Minister Thiruvanchur Radhakrishnan had visited her home or the dance school she runs.
The scam also had its reflection on the factional equations in the Congress in the state as the telephone call details gathered by investigators showed that several ministers and political leaders had made calls to Saritha, apart from getting frequent calls from her.