/var/ directory running out of space

I'm getting a broadcast message on the bash CLI that warns me about the /var/ directory running out of room.

011d0004:3: Disk partition /var has only 14% free

There are four Tomcat files of identical size taking up almost a GB of space, but I don't know what purpose they serve.

-rw-r--r--.  1 tomcat tomcat 240192271 2017-11-05 19:51 1509911444508.upload
-rw-r--r--.  1 tomcat tomcat 240192271 2017-11-05 10:46 1509878765278.upload
-rw-r--r--.  1 tomcat tomcat 240192271 2017-11-05 10:39 1509878372606.upload
-rw-r--r--.  1 tomcat tomcat 240192271 2017-11-05 10:38 1509878267154.upload

Does anyone know what the purpose of these files are, and whether or not it's safe to remove them?