Western Australia has strengthened its border with South Australia amid the state’s growing outbreak.

Effective immediately South Australia will transition to a “low risk” jurisdiction under WA’s controlled border.

Which means travellers will be required to self-quarantine for 14 days and undergo COVID-19 testing.

Recent arrivals into WA from South Australia must get tested if they develop symptoms, and anyone was has been to a South Australian exposure site must isolate for 14 days.

It comes after the state’s COVID-19 outbreak grew to five, plunging South Australia into lockdown from 6pm tonight.

A man who completed hotel quarantine in Sydney returned to Adelaide recently and passed on the virus to four others.

The lockdown is expected to last for at least seven days.

Meanwhile, ten crew members from the BBC California, which is docked at Fremantle, have now tested positive to COVID-19.

Two returned positive tests this morning, bringing the state’s number of total  active cases to 17.

(Photo:Matt Jelonek/Getty Images)