billion bid for Bermuda-based ADT Ltd., a move designed to make it the largest provider of electronic security services in the U.S.

Western offered $22.50 a share in cash and stock for the 73 percent of ADT it doesn't own, 12 percent more than ADT's closing price yesterday. The offer comes less than two months after Western, ADT's largest shareholder, fended off a $4 billion offer from Republic Industries Inc. -- part-owned by Bermuda resident Michael DeGroote -- that was worth more per share.

Topeka, Kansas-based Western, until recently only an electric and natural gas utility, is betting a wider menu of products will help improve profits as well as lure customers from lower-cost power sellers after US electricity sales are deregulated over the next few years.

"They see it as a way of getting more services into the home on one bill,'' said John Lennon, manager of the Colonial Utilities Fund, which owned 400,000 Western Resources shares on November 29.

ADT urged shareholders to wait for its response before accepting the offer.

Western said it won't acquire additional shares until it can replace ADT's board and remove "poison pill'' takeover defences adopted last month that will be triggered if Western increases its stake.

Only on Monday, Western announced it is buying Westinghouse Electric Corp.'s home security business for $425 million in cash and assumed debt, adding 300,000 customers to the 110,000 already served by Western's Westar security unit. ADT supplies alarm systems and electronic monitoring to 1.7 million customers.

Western Resources shares rose 1/8 to 31 3/8. Shares in ADT rose 3 1/8 to 23 1/4 on trading of 7.5 million shares, more than eight times the daily average over the last three months.

The takeover offer concerns some analysts, who noted it could reduce earnings per share as much as ten percent and further weaken Western Resources' financial position.

In addition to the Westinghouse acquisition, the Topeka, Kansas utility also has offered $1.9 billion in stock to acquire neighboring Kansas City Power & Light Co. Western would take on $834 million in Kansas City Power debt if its bid succeeds.

Standard & Poor's Corp. threatened to lower debt ratings for Western's bonds as much as two notches to BBB if the ADT transaction goes through, saying "in the absence of further equity issuances, the company's financial condition will erode.'' BBB is the last rating above junk grade.

Western Resources Chairman John Hayes Jr. said the acquisition will immediately boost cash flow and result in increased earnings per share "in just a few years.'' Buying ADT will actually increase Western Resources' ability to pay dividends, he added.

Western Resources said it will pay $15 in stock and $7.50 in cash for each of 73 percent of ADT shares it doesn't already own. It will also assume more than $700 million in debt and may have to buy back warrants issued to Republic under the aborted takeover agreement. Western Resources today sued to cancel those warrants, which give Republic the right to buy 15 million shares at $20 each.

If ADT continues to resist, Western can increase its bid without overpaying, said Andrew Jeffrey, analyst with Robertson Stephens. The offer now is still about eight percent less than Western paid for Westinghouse's security unit based on multiple of monthly revenue.

Western is positioned "wonderfully to get a deal done somewhere around $25 a share,'' he said.