BEIJING, May 6 (Xinhua) -- Beijing extended its real estate restrictions in an eastern suburban district on Thursday to cover business property to force out speculators.

Families without household registration in Beijing, unmarried Beijing residents who already own homes and families that own more than one home are among those no longer eligible to purchase corporate apartments in Tongzhou District under the new property rules jointly issued by the Beijing Municipal Commission of Housing and Urban-Rural Development and the municipal government of Tongzhou District.

Tongzhou has been increasingly targeted by property speculators, who are betting that its designation as the new administrative center for Beijing will raise the value of real estate in the district.

Those from outside Beijing will only be allowed to buy corporate apartments in the district if they have made tax and social security payments in Beijing for over five straight years.

The rules also stipulate that office space can only be sold to companies for business purposes.

Authorities previously introduced restrictions on residential property purchases in the district in August last year to curb speculation that sent home prices soaring.

Yet speculators have since begun grabbing up business properties in the district, some of which have been converted into residential units for home buyers.

Regulators said they fear this practice, if not effectively tackled, could potentially lead to more population influx than the district is prepared to handle and hurt the district's ability to house businesses if office space is not used for its original purpose.