Shenzhen Metro Lines 2 and 3 will be extended, the local planning bureau said Wednesday.

The extension project plan has been posted on the bureau's Web site www.szplan.gov.cn for public review.

According to the plan, Line 2 will be extended 17.2 kilometers towards the east from Window of the World to Dongmen in Luohu District.

Line 3 will be extended 8.8 kilometers towards the south from Coco Park in the central business area to the Yitiancun housing community in Futian District.

Line 2 was previously supposed to be 24 kilometers long, connecting central Shenzhen with Nanshan District.

It will allow passengers to transfer to Line 1 at Window of the World.

Line 3, under the previous plan, was to link downtown Shenzhen with Longgang District, a total distance of 39.2 kilometers.

Shenzhen became the fifth Chinese city to have an underground rail system after Line 1 was put into use in 2004.

Metro Line 1 runs between the Shenzhen Railway Station in Luohu District and Window of the World.

Construction on the extension of Line 1, from Window of the World to the airport began last year.

Mayor Xu Zongheng said at the annual session of the Shenzhen Municipal Congress last week that Shenzhen will speed up subway construction.

When the projects are finished by 2011, the city's Metro lines will extend 177 kilometers, twice as long as in Hong Kong.

Xu also said Shenzhen will start preliminary research on Line 6, between the airport and Longhua in Bao'an District and Line 8, which will link downtown Shenzhen with Dameisha and Xiaomeisha beaches in Yantian.

Line 4 is a 21-kilometer two-way track between Huanggang and Longhua New Town, with 14 stations. The section between Fumin Road and the Children's Palace is currently in service. The next phase of Line 4 will link the Children's Palace and central Longhua in northern Shenzhen, which will be completed in 2009.

Editor: Yan