The state of Maryland took control of First Maryland Savings and Loan Inc. today, extending a withdrawal ban at the crippled Silver Spring thrift for an additional 90 days, slashing interest on 35,000 depositor accounts and demanding the resignation of the association's top officers.

Baltimore Circuit Court Judge Joseph H.H. Kaplan ordered First Maryland into government conservatorship at 2:38 p.m. and placed it under the control of the Maryland Deposit Insurance Fund (MDIF), which is also managing two other debt-ridden savings and loans: Old Court, a Baltimore thrift that has been placed in receivership so that its assets can be liquidated, and Community, a Bethesda association also in conservatorship. The three thrifts now managed by MDIF have more than 100,000 depositors.

Kaplan's order came four hours after federal officials rejected a last-ditch effort by First Maryland to obtain deposit insurance and is another clear signal that the savings and loan crisis that began in Maryland last May is far from over and represents a deepening fiscal problem for the state.

By taking control of First Maryland today, MDIF also assumed the thrift's $22 million debt, a burden to a state government already grappling with estimated debts of $175 million and $100 million at Old Court and Community, respectively. The state controls an old thrift industry insurance fund of $150 million that could be used to help cover those debts.

In addition to the financial nightmare, the First Maryland conservatorship also marks the beginning of a monumental bureaucratic tangle for state officials, private lawyers and depositors. MDIF Director Melville S. Brown said First Maryland's depositors will receive applications for hardship withdrawals starting next week.

As he has done with other frozen thrifts, Kaplan cut the interest rate on all First Maryland depositor accounts to 5 1/2 percent. Certificates of deposit will continue to earn their original interest until they mature.

Brown, who said First Maryland now has $18 million worth of bad loans and would need $26 million more to qualify for federal insurance, added he would ask for the resignation of First Maryland President Julian M. Seidel, two senior vice presidents and three other vice presidents.

As the official conservator of First Maryland, Brown has the power to fire those officers but said he expects them to comply with the resignation request.

Seidel, the single largest First Maryland stockholder with 35 to 40 percent of its shares and the driving force behind the association's growth over the last 10 years, will be allowed to retain his stock under the terms of the conservatorship. But whether the stock will have substantial value over time remains uncertain, Brown said.

The MDIF director said the stock's value may be impaired because of the severe debt at First Maryland; in addition, Seidel's claim to the stock might be secondary to those of depositors and creditors if all or part of the thrift is liquidated, he added.

Brown, saying his chief goal is to return deposits to First Maryland customers, said he will attempt to negotiate "an orderly merger or a partial acquisition" of the thrift by a healthy financial institution.

"The beat goes on," Brown said today after briefing reporters about what he said were a series of questionable investments by First Maryland, the state's seventh largest thrift with $400 million in assets. Those investments, he said, severely weakened the thrift's financial ealth and prompted state officials to prepare for a conservatorship last August.

It was during that month that First Maryland, hurt like many other state thrifts by massive withdrawals from depositors who could take $1,000 a month, launched a concerted effort to stem the flow.

Between February and August, the drain on First Maryland accounts reduced the thrift's total savings by $63 million, or 25 percent, according to documents filed today with Kaplan.

During August, First Maryland borrowed $25.7 million from MDIF and $36.7 million from the Federal Reserve Bank in Richmond to replenish its depleted cash reserves, according to court documents.

But the run continued, and on Aug. 23 Gov. Harry Hughes banned withdrawals at First Maryland for 60 days at the thrift's request.

Hughes and other officials pinned their hopes for a First Maryland rescue on a subsidiary of the New York banking giant Citicorp, which began negotiating a possible takeover of the thrift this summer.

With no corporate suitor in sight, First Maryland turned to private investors and on Oct. 22 Hughes extended the withdrawal ban for an additional 30 days.

That extended ban would have expired this Thursday. State officials, believing that First Maryland could raise no more cash, prepared to place it in conservatorship.

With the deadline looming, First Maryland officers made their final appeal today for federal insurance, saying they had lined up investors with sufficient capital to satisfy federal regulators.

Also, Seidel, his senior managers and board of directors offered to resign their posts if the Federal Home Loan Bank Board granted the association federal insurance.

But after a 90-minute meeting with Seidel and Maryland officials in Washington, a key Bank Board official refused to approve First Maryland's plan.

"It was an accounting solution on paper that had not solved the real problems" of First Maryland's staggering debt, said Brown, who attended the meeting.

After federal authorities refused to accept First Maryland's proposal, state officials acted swiftly to force the association into conservatorship. At 1:10 p.m. the necessary legal paperwork was filed in Montgomery County, where First Maryland maintains its headquarters; five minutes later, the state's chief judge transferred the conservatorship to Judge Kaplan in Baltimore.

By 2:30, Deputy Attorney General Dennis M. Sweeney was standing before Kaplan to request the conservatorship.

Meanwhile, MDIF took steps to secure First Maryland's offices, computers and files. Brown said the locks would be changed on the thrift's doors and the state has hired a private security firm to guard the association's facilities.