The notice was issued in the wake of a complaint by CPM MLA James Mathew that the ED's action constituted a breach of privilege.
Though there were reports that Jose, Santhosh and Sivasankar were interrogated together, ED officials did not confirm it.
The Kerala High Court on Tuesday stayed for two months the CBI probe into alleged irregularities in the 'Life Mission'.
The CBI has booked Santhosh Eapan of Unitac Builders, which bagged the contract of the project, and carried out searches at his office and residence in Kochi.
Wadakkanchery MLA Anil Akkara said that the vigilance probe could not be accepted. The vigilance probe was announced at a time when the CBI was coming up with an investigation.
The Opposition Leader also made a jibe at the CPI leadership and its secretary Kanam Rajendran.
Chennithala said when the LDF Government has not been releasing the documents pertaining to the Life Mission, it evokes further suspicion.