A civil emergency was declared here yesterday after more than 200 fires, most believed set by arsonists, flared throughout the city during a firefighters' strike.

Mayor Wyeth Chandler announced the emergency, imposed a 10 p.m.-to-6 a.m. curfew and ordered a ban on the sale of gasoline in cans. He said he acted after National Guardsmen and city fire administrators fought unsuccessfuly through Saturday night to keep up with the fires in the first day of the strike by the city's 1,400 firefighters.

Fire officials said the more than 200 blazes amounted to five times the average for a 24-hour period.

Most of the damage seemed to have centered in the residential midtown area. A number of blazes erupted near Overton Square, the center of the city's nightlife. Among the shops damaged were a pet store, a musical instrument store, a restaurant and a nightclub. In another section of the city, four public schools were heavily damaged. Only minor injuries were reported.

Officials said 90 percent of the blazes apparently were deliberately set. They were unable to pinpoint who was responsible, but apparently believed that vandals were not entirely responsible.

"A bunch of nuts ran wild in our community last night." Chandler told a press conference at the National Guard armory.

Police Director E. Winslow Chapman said three striking firemen had been arrested - two were charged with arson and the third with aggravated assault for allegedly resisting arrest after he was stopped for carrying container of gasoline in his car.

Union officials denied responsibility for the fires.

"Firemen in this city are not in the business of burning Memphis down," said Jim Shaw, a member of the executive board of the firefighters' local. "We are professionals in the business of keeping the city free of fires. But when you get a situation like this, vandals will become active and you've got a lot of people who would like to collect money from fire insurance."

Shaw was one of 12 union officials fired by the mayor when the strike began. Mayor Chandler said other strikers also would be fired once they are identified.

Tennessee law does not allow public employes to strike, although they have a constitutional right to organize into bargaining units.

An impasse in negotiations with the firefighters, who are represented by Local 1784 of the International Association of Fire Fighters (AFL-CIO), was reached last week. Union bargainers insisted on night differential pay received by other city employes. The administration refused to discuss it.

"The shift differential was the straw that broke the camel's back," Shaw said.

City officials refuse to resume talks until the firefighters return to work. Union officials said last night they have no plans to call a halt to the strike. A court hearing was set for this afternoon on the city's request for a restraining order sending the firemen back to work.

The city seemed to be taking the strike in stride. Residents in midtown were out in 95-degree heat yesterday observing fire department officials and National Guardsmen dousing the still-smoldering buildings. Gov. Ray Blanton has sent 860 Army and Air Guardsmen plus 102 state forestry firefighters to Memphis. They are aided by 134 volunteers from the Memphis Naval Air Station.