Afghanistan, still tense from a coup during the weekend in which its former president reportedly was either wounded or killed, was attacked today in a report by Amnesty International for "a consistent pattern of gross violations of human rights" during the past 17 months.

Although Hafizullah Amin, Afghanistan's new president, party leader, prime minister, defense chief and head of the secret police, said in a speech Monday that he would free all political prisoners who were "unnecessarily held," Amnesty International officials in London said they do not expect any easing of human rights violations there.

In its report, released today in London, Amnesty International charged Afghanistan with holding thousands of political prisoners -- at least 12,000 in one Kabul jail -- in overcrowded prisons without charges or trials and with using torture and mass executions.

"It is government policy to imprison any individual or member of a political group whom the government considers to be in actual or potential opposition to its policies," the report concluded.

There was still no word from Afghanistan's capital, Kabul, today in the fate of the former president, Nur Mohammed Taraki, whose resignation for reasons of ill health was announced Sunday.

Contradictory rumors swirled through here and Pakistan about Taraki, including that he died of gunshot wounds he suffered in a shootout Friday in the former royal palace and another that he was wounded, but is still alive.

In his speech, Monday night, Amin made a veiled reference to the type of charges contained in the Amnesty International report when he said, "all atrocities by members of the government will not be tolerated any more."

He also promised to end "unnecessary" repression of the people and "unnecessary" arrests.

But, according to Amnesty International, "political imprisonment is widespread and the pattern of arrests includes all groups opposing the policies of the left-wing People's Democratic Party government."

The political prisoners range from fundamentalist Moslem groups who oppose some of the government's reform measures to Marxist-Leninst and pro-Chinese factions, Amnesty International said.

"Persons of moderate, conservative nationalist or left-wing views not shared by the government are also being held, as are some persons belonging to national minorities," the report said.

Five members of the government, including ministers who later confessed to a coup attempt, also have been arrested. Amnesty International said it believes the confessions were extracted through torture.

These views back a report from Kabul by Associated Press reporter Barry Schlachter, who was told that human-rights violations in Afghanistan are "as bad as in (former president) Idi Amin's Uganda. It's reached a point where you can't trust your own family."

Amnesty International said it has the names of thousands of soldiers and officers, students, businessmen, artists, political party workers, civil servants and journalists who have been jailed on unknown charges without trials.

"The names of these political prisoners cannot be disclosed for fear of reprisals," the report said.

It said there are 12,000 prisoners -- other sources have reported 24,000 -- in Pul-I-Charki prison in Kabul, which was built to hold 6,000 persons.

Among them are 42 women and children, some of whom are reported to be ill, who were "arrested merely for belonging to the family of a political prisoner," Amnesty International said.

The Amnesty International team, headed by Turkish constitutional lawyer Mumtaz Soysal, met with Amin last October while he was still vice premier, but it was not allowed to interview political prisoners who it believed has been tortured.

Afghan authorities have not replied to a detailed memo of the Amnesty International findings, the organization reported.

The report names 33 well-known Afghan citizens and former government officials who were arrested after the April 1978 coup and another 10 persons who have been killed while in government custody. These names have been revealed before; Amnesty International said it feared to publish other names it has because of the risk of retaliation against their families.

"(Soviet paratroopers have gone on a "modified alert" since last Friday's change of government in Afghanistan, according to U.S. officials in Washington. The Soviet Union, which shares a frontier with Afghanistan, has been that country's chief ally for the past 18 months.

(A senior U.S. source said the situation in Kabul is "still confused" five days after an apparent coup.

(State Department spokesman Hodding Carter told reporters, "We had noted increased activity among some Soviet units north of the . . . border. We are unable to confirm the nature or purpose of this activity, but we are continuing to monitor the situation carefully." The United States has frequently said that it was opposed to any outside intervention in Afghanistans affairs.)