Officials with Shanghai Entry-Exit Inspection and Quarantine Bureau said ports have reported more instances of people bringing in invasive speices as exchanges between Shanghai and the world have increased.

Shanghai borders screened 20 million inbound tourists and 12 million parcels last year and blocked more than 7,000 entries involving 124 dangerous non-native species.

They included the Mediterranean fruit fly, which attacks fruit crops and the pine wilt nematode that threatens forests.

Officials say existing regulations stipulate a fine up to 5,000 yuan (about $730) for offenders, but this is not enough of a deterrent, so they will blacklist repeat offenders.

Being blacklisted may be recorded on people's credit and police records, the officials said.

Repeat offenders could face criminal charges once an amendment submitted to the legislature is passed, they added.

The officials did say they would be lenient on those who did not know the species were controlled.