As China’s annual “618” shopping festival – one of the country’s biggest online retail events – gathers momentum, Beijing’s market regulator on Thursday summoned major e-commerce platforms over a series of marketing malpractices, marking the latest effort by authorities to curb so-called involution-style competition.

The Beijing Municipal Bureau of Market Supervision and Administration said it had called in representatives from Alibaba Group Holding’s Taobao and Tmall, JD.com, Pinduoduo, Douyin and RedNote. The agency outlined a series of violations in a notice published on its WeChat account.

Among the issues identified were misleading advertising practices, including “billion-yuan subsidy” campaigns in which actual spending fell short of advertised amounts. The regulator said it had ordered the companies to rectify the problems.

The Beijing agency’s probe came as China’s State Administration for Market Regulation (SAMR) said on Thursday that it had summoned several online travel agencies, including Ctrip and Meituan, over alleged misconduct such as improper marketing of train-ticketing services and the illegal collection of user data.

SAMR said it had urged the companies to comply with laws and regulations, protect consumer rights and avoid unfair competition.

Ctrip and Meituan did not immediately respond to requests for comment.

The moves by both state and Beijing market regulators come as Chinese authorities step up scrutiny of some of the country’s largest internet platforms in an effort to curb excessive competition and restore market order.