Thiruvananthapuram, Nov 18 (IANS): A former top police official who probed the ISRO espionage case will file an appeal in the Kerala High Court after it quashed the state government's order to drop charges against him.

Siby Mathews will go to court after it dismissed an order to drop charges against him and two retired police officers who had implicated and arrested scientist S. Nambi Narayanan in the now infamous ISRO spy case.

"Yes, I have decided to appeal and my lawyers are working out my petition," Mathews, who is currently the state chief information commissioner, said Tuesday.

The move comes at a time when the Kerala government is still undecided on how to go about this case. State Home Minister Ramesh Chennithala has said they will move forward based on legal advice.

In 2011, the Oommen Chandy government decided not to take action against the three police officers following which Narayanan approached the court and got the government's order quashed last month.

The ISRO spy case surfaced in 1994 when Narayanan, along with another top official of ISRO, two Maldivian women and a businessman, was arrested on espionage charges.

But the CBI cleared him in 1995 and since then he has been fighting a legal battle against the three police officials.

The three police officials in question are then top police officer Mathews, K.K. Joshua and S. Vijayan, who are all now retired.

Narayanan said: "I feel that if the present government is really democratic and is bound by the rule of law, they should not go forward."

"All these years, these officials were able to bend successive governments and now a stage has come when the law is staring at them," the former space scientist told reporters.