Two women yesterday admitted planting drugs on behalf of their imprisoned boyfriends in an attempt to turn the men into informants so they could have their sentences reduced. Joyce Ng Mo-sheung, 20, and Bonnie Sung Wing-shuen, 27, pleaded guilty to trying to pervert the course of justice. The other charge of trafficking in a dangerous drug was not proceeded with and left in the court file. The pair planted 251 grams of methamphetamine, or 'ice', at a house in Fairview Park, Yuen Long, between April 1 and May 5 last year, the Court of First Instance heard. Prosecutor Jackson Poon said Sung's boyfriend, Yeung Kar-lam, told police in February last year that he could offer drug information and asked them to contact Ng, a boutique salesgirl. Yeung had been jailed for seven years and four months for trafficking in a dangerous drug. The other boyfriend, Li Wai-yip, was sentenced to four years and nine months' jail after pleading guilty to four drug-related offences. Ng and Sung told police they were willing to provide information and left their contact numbers. The two boyfriends were not charged in the latest case. Deputy Judge Richard Hawkes adjourned the case until today .