MANAGUA, NICARAGUA, FEB. 20 -- Nicaraguan President Daniel Ortega announced a new campaign today against "counterrevolutionary speculators" and warned that the government may jail merchants who do not sell products at state-regulated prices.

As part of the campaign, police and other Sandinista-controlled groups raided several markets here this morning. Witnesses said police confiscated the goods of unlicensed vendors and jailed at least two persons at the Eastern Market, one of Managua's largest.

The steps signaled a hardening of the government's position against the burgeoning number of unlicensed traders in the wake of economic reforms announced Feb. 14 by Ortega. The campaign indicates the Sandinistas will use rigid wage and price controls to fight inflation that reached 1,500 percent in 1987.

Speaking to hundreds of government officials, Ortega warned domestic political opponents and the newspaper La Prensa to "be careful, because they can . . . provoke an insurrection that can destroy them." Ortega said La Prensa and a leading private business group were, along with the United States, "enemies of the revolution."

Ortega warned that "the people" and the government will confiscate stores and taxis that close down rather than accept lower prices. Some businesses refused to open after last week's reforms.

As part of the reforms, Nicaragua revised its currency, issuing new cordobas that are each worth 1,000 old cordobas. The government will try to encourage production by buying goods from producers according to what their products are worth on the market instead of paying according to costs. The government also will abolish a series of subsidies.

Ortega said today that the currency revision took away about 116 billion cordobas, or $5.8 million at the official exchange rate, from black marketeers and antigovernment rebels, who were prevented from exchanging the old currency for the new money.

Ortega also announced that the budgets for all government ministries -- including defense -- will be cut 10 percent as part of the economic reform.

The new campaign against unlicensed merchants goes against a policy begun last year that allowed vendors more freedom to sell at market prices. The government lifted controls in part because it was not able to adequately control markets.

In the sprawling Eastern Market here, vendors vowed to fight the new controls. One merchant, Isabel Castro, said it will be impossible for the vendors to sell at government-set prices unless products are sold to them at lower prices. "We're not doing this to lose money," she said.