LITTLE ROCK, Ark. (AP) — Arkansas reported its biggest one-day spike in coronavirus cases in four months Wednesday, an increase the state’s governor said was being fueled by the delta variant of the virus.

The state reported 686 new virus cases, bringing its total since the pandemic began to 349,385. The state’s active cases, meaning those that don’t include people who have recovered or died from the virus, increased by 398 to 3,763.

The one-day increase in cases was the state’s highest since it reported 726 on Feb. 25.

The state’s COVID-19 hospitalizations increased by 19 to 325 and deaths increased by four to 5,909.

“The high number of cases today makes it clear that the delta variant is increasing the spread of the virus,” Gov. Asa Hutchinson tweeted Wednesday afternoon. Hutchinson, however, said the good news was that the state reported more than 10,000 new vaccinations.

The delta variant of the coronavirus that causes COVID-19 was first detected in India.

Arkansas has had one of the lowest vaccination rates in the country. Nearly 42% of the state’s population has received at least one dose of the vaccine and about 34% have completed their vaccination, according to the Centers for Disease Control and Prevention.