The Justice Ministry will toughen its immigration procedures by using past data to profile people who would be likely to stay on illegally in Japan, according to ministry officials.

In particular, the ministry is keen to bolster scrutiny of arrivals on short-stay visas, given that screening of this category of visitor has been less rigorous than for those who hold student visas, even though short-stay visa-holders are a greater source of illegal residents, the officials said.

The ministry hopes to introduce the new procedures this month.

People who enter on short-stay visas account for 70 percent of the roughly 220,000 illegal residents in Japan.

Profiling will be based on past data collected on illegal foreign residents, classifying them by country, age, place of residence or host organization.

Based on this information, immigration authorities will be on the lookout for foreigners who match one or more of these categories.

Immigration officials at airports will conduct special individual screening for entrants who fit the profile.

If the entrants are arriving on tourist visas, for example, the officials will examine if they have sufficient funds for the planned stay. If the entrants are visiting on "short-term business purposes," officials will try to confirm whether their host companies actually made such appointments.

The new measures are a key component of a government initiative to halve the number of foreigners living illegally in Japan within five years.

According to the ministry, about 4.3 million foreigners came to Japan on short-term visits in 2002.

The second-largest group of illegal residents consists of those who arrived on entertainment visas. A number of people arriving here as "dancers," for example, end up being forced to work as bar hostesses by "talent agents" who are in fact linked to the underworld, immigration authorities say.