MOSCOW, DEC. 22 -- The head of the KGB warned today that the Soviet Union must be prepared to "accept the possibility of bloodshed if we are to bring about order" in the rebellious republics, and he accused the CIA and other Western intelligence agencies of helping to "mastermind" this nation's collapse.

KGB secret police chief Vladimir Kryuchkov's hard-line speech at the Congress of People's Deputies struck many liberal lawmakers as a return to the rhetoric of the Cold War and as further evidence that the Soviet leadership has taken a decisive turn toward authoritarian tactics. In his resignation speech Thursday, Foreign Minister Eduard Shevardnadze warned of a return to dictatorial rule.

In the Latvian capital, Riga, today, more than 500 Soviet officers in the Baltic military command issued a declaration saying that if the congress fails to take concrete measures "establishing public order and political stability" in the country, "you will force us in the Baltics to take all possible measures up to and including martial law to defend our rights and honor."

"The army is the only power to preserve the {Soviet} Union," said one of the Baltic military leaders, Gen. Valentin Filatov, according to the Baltic News Service. The officers also pledged that any attempts to cut off supplies to army bases would result in the army "taking direct control of all the energy and electrical systems, water and heating sources."

Also today, Soviet President Mikhail Gorbachev, who has warned that he is prepared to institute direct presidential rule in the country's ethnic "hot spots," said he would give the Russian and Gagauz ethnic minorities in Moldavia 10 days to end their division with the republic. Otherwise, he said, he would take "necessary steps."

The Russian- and Turkic-speaking minorities have tried to establish independent republics, but Gorbachev has declared those actions invalid. He also said the Romanian-speaking majority in Moldavia must reconsider legislation that the two minority populations have called discriminatory against them.

Kryuchkov today angrily accused the CIA and other Western intelligence agencies of increasing their espionage activities, trying to derail the Soviet economy, gathering information on workers' movements, funding "anti-Soviet organizations" such as Radio Liberty, aiding secessionist groups in the republics and "inspiring" the mass emigration of scientists, artists and other intellectuals.

He also accused the West of selling spoiled grain to the Soviet Union.

"Exploiting our own mismanagement, they supply the Soviet Union with weedy and sometimes contaminated grain and foodstuffs with higher radioactivity and harmful chemical admixtures," Kryuchkov said, adding that about half of all the grain sent here "contains weeds" or is "unusable."

The KGB chief also made clear that the Soviet security forces expect armed struggle with what he said were a total of 26,000 local security troops in the Ukraine, Latvia, Estonia, Georgia and Armenia. He said emigre groups were aiding armed nationalists.

"The KGB is convinced that if the country continues in this vein, it will lead to chaos," Kryuchkov said. His speech to the congress was even more emphatic than a television address earlier this month in which he pledged that the secret police would do battle with "the wave of anti-Communist forces."

Kryuchkov's speech, coupled with Shevardnadze's resignation, has left many of the reformers at the congress depressed.

"Listening to Kryuchkov, you realize that the KGB has not changed its thinking one iota," said Oleg Kalugin, a former KGB major general who is now a legislator and an ardent critic of the secret police. "It's amazing that he can talk that way when you think of all the food aid arriving from the West."

Kryuchkov and Defense Minister Dmitri Yazov have taken a particularly high profile in recent months, while reformers such as Shevardnadze and former Politburo member Alexander Yakovlev have left the political stage.

The official news agency Tass said Shevardnadze agreed during a meeting with Gorbachev Friday that he would participate in the drafting of a U.S.-Soviet treaty on strategic weapons and continue in his post until a successor is found. "This confirms that the country's foreign policy is immutable," Tass said,

Sociologist Tatyana Zaslavskaya, one of Gorbachev's earliest supporters, said the leadership's turn to a hard-line policy is "undeniable." She said Soviet society, "which has no experience or profound expectations of democracy," is creating a public expectation for greater order. The structures of the KGB, the army and the Communist Party are exploiting that mood to "save their own skins," she added.

Zaslavskaya said a poll just conducted by her academic institute shows that 22 percent of the population -- "a surprisingly large minority" -- says it would welcome a military coup. In another poll, she said, when people were asked what the country most lacked, 56 percent answered "genuine power."

Some of the key reformers in Gorbachev's camp have grown disgusted with the recent political turn. Stanislav Shatalin, author of a radical economic plan for a 500-day transition to a market economy, said that after Gorbachev's early support for the plan, his eventual decision to "water it down to nothing" was "inexplicable."

"I simply don't know what to say," Shatalin said. "I respect Gorbachev -- maybe that is my weakness -- but I can only do what I have done already. His decisions baffle me completely."

Baltic leaders said Gorbachev already has allowed the KGB and the army to begin asserting their authority in the region. They said the officers' action in Riga may only be a prelude to declaration of presidential or martial law in the Baltics.

Soviet troops armed with submachine guns are now patrolling the Lithuanian port city of Klaipeda and making spot checks of people's documents. According to Col. Ivan Chernych, the Klaipeda garrison commander, the soldiers are under orders to arrest anyone who resists the document checks.

The mayor of Klaipeda, Vytautas Cepas, called the patrols "an open provocation." The Lithuanian parliament sent a message of protest to Gorbachev asking him to order an end to the patrols "and punish {the military} for their willful behavior."