BANGKOK, Feb. 8 (UPI) -- Burmese artillery and mortar shells pounded the last major base of the ethnic Karen resistance Wednesday in an offensive military analysts said could bring the rebels' 47-year independence struggle to an end.
Provincial officials monitoring the fighting in Burma said they counted more than 600 explosions in the Karen base of Kawmoora, opposite the Thai border town of Mae Sot, located some 240 miles (386 km) northwest of Bangkok, in the past two days.
They said about 25 shells landed on the Thai side of the border, which is only 545 yards (500 m) from Kawmoora, prompting Thai gunners to retaliate Wednesday with several salvos of artillery and mortar fire into Burma to warn the attackers.
Thai military officers said a final Burmese infantry assault on the battered Karen base could come at any time.
The Karen, many of whom were converted to Christianity in the late 19th century by American Baptist missionaries, have been in almost continuous revolt against Rangoon since Burma won independence from Great Britain in 1948.
"The Burmese government has almost finished consolidating," a senior Thai military officer told United Press International. "If they take Kawmoora the Karen will be finished."
The Burmese, armed with newly purchased Chinese AK-47 assault rifles, heavy artillery and other weapons, captured the Karens' self-proclaimed "capital" of Manerplaw on Jan. 27.
Manerplaw had been the headquarters of the rebel Karen National Union for the past 21 years as well as the main "liberated area" of Burma's pro-democracy forces since the current military junta seized control in Rangoon in 1988.
The junta, known as the State Law and Order Restoration Council (SLORC), has consolidated its grip on the country by negotiating cease- fires with several rebel groups and attacking others militarily.
United Nations officials said the Burmese offensive has forced about 10,000 Karen refugees to flee into Thailand, in addition to about 60,000 Karen who have fled previous attacks.
The U.N. High Commissioner for Refugees representative in Thailand, Ruprecht Von Arnim, said the Thai army was providing food, medicine and shelter to the latest wave of refugees.
He said between 1,500 and 2,000 Karen were returned to Burma voluntarily earlier this week in an area where fighting had died down. Karen National Union representatives said that since the fall of Manerplaw their forces had split into small guerrilla units to carry out hit-and-run attacks on the Burmese.
But analysts said that without funds from cross-border taxes and aid from Christian supporters the Karen insurgency seemed hopeless. "The Karen are just trying to hang on," the senior Thai military officer said. "They have been pushed out of their land into Thailand. Next (the SLORC) will turn their attention to Khun Sa."
With the Karen resistance shattered, the only major rebel force opposing the junta is the 20,000-strong Muang Tai Army, led by the infamous Shan "opium warlord" Khun Sa.
Khun Sa admits he derives most of his income from taxing opium caravans and heroin refineries in Burma's Shan State, but denies direct involvement in narcotics trafficking.
"Khun Sa will be more difficult to defeat," the Thai officer said. "He relies on his own weapons and his own opium."