AIRLINES

Denver Sues Continental Airlines: The city and county of Denver filed suit against Houston-based Continental Airlines Inc., alleging violations of its lease terms at Denver International Airport, which opens Tuesday. Continental was the first airline to lease space at Denver International and it is now committed to lease 20 gates and pay fees based on a minimum of 6 million passengers annually for five years. The carrier maintains it will pay only for the gates it uses. Continental said last week that it will cut its service at Denver to 15 daily flights April 1, from 139 in January, 1994. The carrier and city aviation officials had been negotiating a revision to the lease that would require Continental to pay about $65 each for its 704,000 passengers who start or end their journeys in Denver.