Britain's FTSE-100 index closed higher on Friday, with shares immune to the economic cycle such as healthcare firm Smith & Nephew leading the way.
Traders said news Pakistani troops had cornered a group of al Qaeda militants, which may include Osama bin Laden's deputy, had supported the index as it recovered from Thursday's 60-point battering on renewed security worries.
The index closed 19.8 points higher at 4,417.7, riding out quarterly expirations of UK futures and options and tracking a volatile Wall Street which moved above early lows as it faced its own derivatives expires.
Traders said investors had closed short positions and bought defensive shares, not wanting to be caught out in case bin Laden's deputy, Ayman al-Zawahiri, was captured over the weekend.
"If you look at next week the market hasn't got much to feed off in terms of results. If Pakistan are pretty close to getting this guy, do you want to take a risk and leave yourself short ahead of the weekend?" said one trader.
Smith & Nephew, recently the subject of unfocused bid talk, was top FTSE gainer, up four percent, while cruise operator Carnival climbed 3.3 percent before first-quarter results due on Monday.
Continuing the defensive theme, drinks-can maker Rexam rose 3.2 percent while bulk gas and power network operator National Grid Transco advanced 2.6 percent.
Packaging group Bunzl was a major gainer, up 2.7 percent on speculation it was a front-runner to buy UK vending machine company Autobar, which analysts say could boost Bunzl's bottom line.
Among other blue chip gainers, mobile phone operator mmO2 rose three percent after Morgan Stanley gave the stock an "overweight" rating.
Builders' shares crowded the list of FTSE Midcap 250 gainers as Persimmon Plc triggered speculation it was looking for acquisitions after Britain's biggest house-builder said it had appointed a new adviser.
Persimmon rose 4.4 percent.
"I think there is going to be more consolidation in the sector. The right acquisition at the right price and Persimmon would be there for it. That appointment has given us a bit of a clue that they're serious about it," said Tony Craze, analyst at Goy Harris Cartwright Stockbrokers.
Westbury rose 5.9 percent and Redrow put on 5.8 percent. Building material stocks RMC and Aggregate Industries each rose more than one percent.
Upmarket stove maker AGA Foodservice was another mid-cap feature, up 6.9 percent after saying 2004 had started well and new products were ready.