According to the ACB sources, Patel was questioned for more than three hours.
He arrived at the ACB office around 11.15 a.m. and was questioned till 2.30 p.m.
The ACB had summoned Patel on Sunday after rebel and sacked Delhi Minister Kapil Mishra told the ACB that two persons -- Patel and Ashish Talwar -- close to Kejriwal were responsible for the delay in action in the water tanker scam.
An ACB offical related to the probe told IANS: "Patel has denied any involvement in the matter. Thus, we will once again cross-question Mishra on his allegation and if required, Patel would also be told to join the probe."
Mishra recorded his statement with the ACB on May 11, after he submitted evidence in support of his allegations that two persons close to Kejriwal tried to influence the scam probe.
Talwar is also likely to be summoned after Patel's statement in the case is recorded, according to the official.
The Rs 400-crore water tanker scam involved alleged favouritism shown in the allotment of contracts to private water tanker operators to supply water to areas not falling under the Delhi Jal Board's network during the previous Congress government in Delhi.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)