OSAKA--Security was heavily tightened at Kansai International Airport from June 27 and traffic severely disrupted as leaders from around the world descended on this major city in central Japan to attend the Group of 20 summit.

Police stopped traffic on about 160 kilometers of the routes making up the Hanshin Expressway to allow for smoother transport of the leaders to the summit venue and elsewhere.

Tight security is expected to continue for the two-day G-20 summit, the first being hosted by Japan, until June 30, the day after its conclusion.

The use of Kansai International Airport by many of the arriving leaders meant other travelers were inconvenienced from June 27. There are no plans to reduce the number of commercial flights into and out of the airport, which is normally used by about 89,000 passengers daily.

Access was restricted to some parts of Terminal 1, including the arrival and departure floors for international flights as well as the floor for domestic flights.

Police officers were standing at the entrances to the terminal and checking that passengers had tickets before being allowed to enter. Those without tickets who had come to see others off had to have their belongings pass through a security check. That led to a longer than usual line in front of the entrance.

Limousine bus services between Kansai International Airport and the major tourist areas in the Kansai region were for the most part canceled. One reason was that traffic on the access bridge connecting the airport to the mainland was closed off to allow only vehicles carrying the leaders attending the summit to go through.

Those measures led to heavy congestion at the Kansai-Kuko train station.

But local residents had taken precautions, with one woman in her 30s explaining that she and her family had left their home in Mino, Osaka Prefecture, at 6 a.m. to catch a noon flight.

Meanwhile, police officers dispatched from prefectural police departments from around Japan were on guard at points on the Hanshin Expressway putting out signs indicating a route was unusable.

Almost all the 10 major routes were closed as of 6 a.m. on June 27. On a normal weekday, about 450,000 vehicles use the closed portions.

An official with Hanshin Expressway Co. said this was likely the first time for such a major closure, except for situations involving natural disasters.

Osaka prefectural police said the expressway closure will continue until about 10 p.m. on June 27. The closure will be repeated from early in the morning until late at night until June 30.

Police were also blocking off traffic on surface streets, especially in areas surrounding the summit venue and around the hotels where the leaders are staying.

Osaka police had asked local residents to refrain from driving during the June 28-29 summit and so far the appeal appeared to be working as there were few signs of major traffic jams on June 27.