Warren Buffett evaded a kidnapping attempt in the 1980s. He's prioritized his personal security ever since.

• Two men tried to kidnap and hold Warren Buffett for ransom in 1987, but their plan failed.
• The investor had a security camera and 300-pound metal door installed in his office afterward.
• Buffett's Berkshire Hathaway spends about $300,000 a year on his personal and home security.

Warren Buffett once evaded an attempt to kidnap and hold him for ransom. The incident woke him up to the risks of being rich and famous, spurred him to invest in heavy-duty security and surveillance equipment, and may explain why he doesn't pinch pennies when it comes to his personal security.

Buffett's decades of shrewd stock purchases and savvy business deals were paying off handsomely by the mid-1980s, author Alice Schroeder wrote in "The Snowball: Warren Buffett and the Business of Life." Forbes included the investor in its list of the 400 wealthiest Americans for the first time in 1985, and Buffett was one of only 14 billionaires in the rankings.

The Berkshire Hathaway CEO, now firmly in the public eye, soon became a target for criminals. Two men, one armed with a chrome-plated replica of a .45 handgun, turned up at Buffett's office building in Omaha, Nebraska in 1987, Schroeder wrote.

The pair planned to abduct the investor and demand $100,000 for his safe return — the equivalent of $245,000 today.

Security guards and the police foiled the plot, but the incident rattled Buffett and those around him. While the Berkshire chief rejected the idea of a personal bodyguard as a constraint on his privacy and freedom, he did have a security camera and a 300-pound metal door installed to safeguard his office, Schroeder said.

Buffett's memory of the gun-wielding kidnapper might explain why Berkshire has spent an average of $339,000 a year on his personal and home security since 2008, according to company filings. The notoriously frugal investor has happily collected a $100,000 annual salary for more than 40 years, but he hasn't skimped on keeping himself safe.