Captain Jasbir Singh Raina of 10 Guards scouted the Golden Temple complex in civilian clothes, then led his company in and was badly wounded.
In Civilian Clothes, Then First Inside
Before the assault of Operation Blue Star, Captain Jasbir Singh Raina of 10 Guards went into the Golden Temple complex at Amritsar in civilian clothes to study its fortifications. Accounts put this on 2 June or 3 June 1984. Wikipedia says militants trailed him throughout and that he came back with useful information on the layout.
On the night of 5/6 June, his B Company was ordered in. By that account, it was the first company to enter, with Raina in the lead. The objective was three-storeyed buildings with tunnels and basements.
The leading platoon came under heavy light machine gun fire from all sides as it passed the main entrance. Raina was hit in the knees at point-blank range and was evacuated, seriously wounded.
From Shimla to 10 Guards
The Ministry of Defence lists him as a resident of Shimla, Himachal Pradesh, and the son of Kartar Singh Raina. His service number is IC-37068.
Wikipedia, citing Gazette notices, says he retired as a colonel on 3 April 2000. His Ashoka Chakra dates to Republic Day 1985.
What the citation recorded
Summary, not the official text: the official awards website records that Captain Jasbir Singh Raina received the Ashoka Chakra for an act of gallantry in Punjab, under Operation Blue Star. Published accounts say he reconnoitred a fortified building in civilian clothes and later led the first company into the complex, where he was seriously wounded.