Texas DPS and Austin Police Department involved in incident on I-35

AUSTIN, Texas - The upper deck of I-35 has been closed for hours due to an incident involving the Austin Police Department and Texas Department of Public Safety.
What is happening on I-35 in Austin?
What we know:
The Austin Police Department posted on social media about the upper deck of I-35 being closed due to an "active law enforcement incident involving DPS."
APD says a large portion of southbound I-35 will be closed from Highway 183 into the downtown area.
What you can do:
People are asked to avoid the area and find alternate routes.
What we don't know:
Details about the incident have not been released at this time.
Video captured by FOX 7 shows a Fort Worth ambulance on the upper deck but there has been no official word on how, or if, the ambulance is involved in the incident.
A news conference is expected at around 9:45 a.m. from DPS.
The Source: Information from Austin Police Department and Texas Department of Public Safety.