PANAMA CITY -- Long a freewheeling shipping hub and offshore banking center for the Americas, Panama is enjoying a building boom on a scale unmatched since the construction of its famous canal 92 years ago.

The country is luring investors and expatriates worldwide, with interest further boosted by the recent approval of a $5.2 billion plan that will double the canal's capacity.

A real estate frenzy fueled by easy credit from Panamanian banks, government incentives, and a saturated US housing market for retirees has attracted speculators and prospective residents from California to Dubai. They are snapping up preconstruction bay-front apartments, highland villas, and the latest luxury development from Donald Trump -- a $220 million residential, office, and hotel complex called Trump Ocean Club, with towers shaped like a yacht sail. Two rival Spanish projects are vying to build the tallest skyscraper in Latin America at about 100 stories

Construction moguls and estate agents say Panama City is a sure bet for investors, offering discount prices for quality of life and healthcare rivaling the United States', more than 100 international banks, tax breaks, and stunning Atlantic and Pacific coastlines

But urban planners and long time residents warn that overbuilding could ultimately strain the country's roads, water supply, and other infrastructure to the breaking point with devastating consequences

Cranes, building sites, glitzy sales offices, and real estate package tours aimed at foreigners are everywhere, from Avenida Balboa in downtown Panama City to suburban Punta del Este. Laundered drug money from neighboring Colombia built some of the early mirrored high-rises in the 1980s, but today's buyers include fixed- income senior citizens from the United States searching for a less expensive place to retire as well as billionaires from Monaco and Cannes.