According to the Immigration and Checkpoints Authority, a an attempt to import Chinese Liquor and e-vaporisers were foiled by the officers.
The case has since been referred to HSA and Singapore Customs for investigations.
Here is what ICA said:

On 17 May, ICA officers at Tanjong Pagar Scanning Station foiled an attempt to smuggle in 145 e-vaporisers and 20 bottles of Chinese liquor via an inbound container.
Our officers had noticed anomalies in the scanned images of the container and an unstuffing operation was conducted at the importer’s premises. The contraband was uncovered in the consignment declared as “consolidated items”.
The case was referred to Health Sciences Authority and Singapore Customs for further investigation. In a follow-up operation by Singapore Customs, one male Chinese national was arrested.


Penalties:
HSA would like to remind the public that the Tobacco (Control of Advertisements and Sale) Act prohibits the import, distribution, sale or offer for sale of harmful or imitation tobacco products. These include shisha tobacco, smokeless tobacco, chewing tobacco such as Gutkha, Khaini, Zarda, electronic vaporisers and their accessories.
Any person convicted of an offence is liable to a fine of up to $10,000, or imprisonment of up to six months or both for the first offence, and a fine of up to $20,000, or imprisonment of up to 12 months or both for the second or subsequent offence. All prohibited tobacco products will be seized and confiscated.
Image Source: ICA