Internal corruption may have cost DJI Technology Co. Ltd. 1 billion yuan ($150 million) in 2018 for overspending on procurement, the Chinese drone maker said.

Shenzhen-based DJI, the world’s largest consumer drone manufacturer, has set up an internal inspection team to investigate the cases, DJI told Caixin Friday.

An internal company report seen by Caixin showed that about 45 employees have been punished, including some who are being handed over to law enforcement departments. Most of the corruption cases are linked to the DJI supply chain management and procurement department.

According to the report, some employees have taken kickbacks from suppliers or colluded with research people to grant favors to certain suppliers. The investigation has detected large-scale corruption in the company that may involve over 100 people, the report found.

DJI has yet to publish its 2018 results. The company posted 18 billion yuan of sales revenue in 2017, up 80% from the previous year.

Chinese tech giants have stepped up efforts to fight internal corruption. Earlier this month, ride-hailing company Didi Chuxing said its compliance staff found more than 60 cases of corruption within the company last year. A total of 83 people were dismissed for “severe violations” of company rules, Didi said.

Other tech leaders, including Baidu, Tencent, JD.com and Xiaomi have also previously reported cases of employee graft.

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