Business in smuggling Afghan refugees across the Indian-Pakistani border is thriving since the two nations have barred the movement of most Afghans--including some with legal passports and visas--from one country to the other.

The smuggling operation costs $300 a person, according to reliable Afghan refugee sources here, and is considered perfectly safe since no one reportedly has been caught by border guards from either country.

"There is no problem," said an Afghan with a smile. "You just give me $300, and I'll even get you across."

One man, who is still listed as working in the office of the Afghan prime minister in Kabul, plans to smuggle his wife and four children from Pakistan into India. The man, 36, came here on a legal visa issued so he could receive medical treatment.

Before he arrived last month, however, he made sure that his family had made the tricky crossing through the Khyber Pass into Pakistan, where they are among 2.5 million refugees. He asked that his name not be used to protect relatives still in Afghanistan.

To bring his wife and children here poses a problem because India has refused since late October to admit Afghans coming from Pakistan.

The Indian government said at the time that too many Afghans were traveling on false passports and forged visas, many of them crudely made in back-room print shops in Pakistan's Khyber Pass city of Peshawar.

Former Afghan government official Siad Mohammed Maiwand, an outspoken refugee leader here, accused India of bowing to pressure from the Soviets and the Soviet-backed Afghan government in refusing to allow Afghans into this country from Pakistan.

About 20,000 to 30,000 Afghan refugees are living in India, and about 8,000 of them have registered with the United Nations High Commissioner for Refugees, which recently reopened its Delhi office. While the Afghans have not been granted refugee status here by the Indian government, they have been allowed to remain in the country.

The Afghans who come here tend to be the elite--former government officials, teachers and businessmen--who prefer the greater freedom and increased opportunities of India.

Maiwand, for instance, said he would refuse to live under Pakistan's martial-law government, especially since he had been jailed by a previous military government there.

But since most of the refugees come out of Pakistan on foot without passports, the new Indian rules make it nearly impossible for them to move legally to India.

It is unclear whether the smugglers of refugees are Afghans or Indians and Pakistanis. Excluding 335 miles of disputed boundary in the Kashmir area in which troops are on a constant military alert, India and Pakistan have a common border of 1,300 miles that is reportedly easy to cross. Much of the border is flat land, some uninhabited desert that is patrolled by camel corps on both sides.

Goods smuggling has been rife across the border--with Indian liquor going into Pakistan, where Islamic law forbids the consumption of alcoholic beverages, and imported merchandise moving to India, where it is either banned or prohibitively expensive because of high tariffs.

Only recently has the trade in people become a part of the smuggling operation.

It all started in late October, when India refused entry to 41 Afghans on an Indian Airlines flight from Lahore, Pakistan, to New Delhi. The officials said the Afghans' passports were phony and the Indian visas forged.

A few days later, 55 more Afghans coming from Pakistan--some with legal Afghan passports and legitimate visas issued by the Indian Embassy in Kabul--were denied entry.

In what turned out to be an international game of refugee Ping-Pong, Pakistan then refused to allow the Afghans back in that country.

Finally, most of the 96 dispersed. Some went back to Kabul while others flew to the nearby Nepalese capital of Katmandu.

After spending close to a month camping out in the transit lounge of Delhi airport, 22 were allowed to remain here on humanitarian grounds. The Indian government, however, refused to grant them political refugee status.

Pakistan clamped its restrictions on Afghans coming from India soon after New Delhi issued its ban.

It is possible for Afghans to get visas in India for entry to Pakistan, but only with great time-consuming effort.