A senior official of the financial probe agency told IANS: "We have attached six properties of Karti worth Rs 54 crore."

The properties attached include a cottage worth Rs 8.67 crore in the UK's Somerset, a tennis club and land located in Spain's Gava worth Rs 14 crore.

The ED also attached land and properties worth Rs 16 crore in New Delhi's Jor Bagh area (Karti's mother Nalini Chidambaram is also a stake holder of 50 per cent in the land), a bungalow in Tamil Nadu's Ooty worth Rs 50 lakh and another one worth Rs 3.75 crore in Ooty and an agricultural land worth Rs 25 lakh in Kodaikanal.

The ED has also attached properties belonging to Peter and Indrani Mukerjea in connection with the same case.

The properties were attached under the section of Prevention of Money Laundering Act (PMLA).

Karti is facing probes by the ED and the Central Bureau of Investigation (CBI) in several cases, including alleged irregularities in the Foreign Investment Promotion Board clearance to then INX Media for FDI in 2007 and the Aircel-Maxis case in 2006 and a money laundering case.

The ED and the CBI are probing how Karti managed to get clearance from the Foreign Investment Promotion Board (FIPB) when his father was in office.

Karti was arrested on February 28 by the CBI for allegedly taking money to facilitate the FIPB clearance to INX Media in 2007. He was later granted bail.