Police are speaking to homeless charities to try to trace 52-year-old David Harold Hraboweckyj.
Officers are extremely concerned for the safety of Mr Hraboweckyj, who left his home in Charles Road, St Leonards, on the morning of Monday 16 September and has not been seen since.
Mr Hraboweckyj is a paranoid schizophrenic who last took his medication on the day he disappeared.
It is believed that it has been so long since he took his medication that he could now pose a danger to the public if challenged.
Police are appealing for witnesses in St Leonards who may have seen a gang, who were carrying weapons, chase three men.
It is thought the gang were carrying a sword and a claw hammer, but the weapons were not used on anyone.
A 22-year-old man and a 23-year-old man, both from St Leonards, were questioned on suspicion of public order offences before being released on bail until 23 September.
PC Ian Rise, from Hastings Response Investigation Team, said: "We believe that an argument happened, causing all six men to run into the street."
A pet cat was left with a broken jaw and a seriously swollen face after being attacked.
A police spokesman said, "The vet believes that the injuries were not caused by a vehicle or another animal but in a malicious attack."
Officers are investigating the possibility that it may have been thrown from a height.
The pet was found by it's owner on Albany Road, St Leonards, at around 9pm on 18th July. She was so distressed by the cats injuries that she did not report the incident until several weeks later.
Anyone with information should call 101 quoting serial 595 of 5 August.
The victim was left extremely upset and distressed by what happened and we are very keen to trace the man responsible. He is described as white, in his mid 20s, wearing cream shorts, a grey hooded top and a red baseball cap. Anyone with information is asked to contact Sussex Police on 101, quoting reference 1222 of 23 March. Alternatively, call the independent charity Crimestoppers anonymously on 0800 555111.
Police in Hastings are trying to trace a man who racially abused a teenage girl in St Leonards on Saturday 23 March. The 13-year-old was with two friends in Kent Road when the incident took place at about 7.40pm. After shouting the abuse, the girls ran away and called police.
The fire in Menzies Road, St Leonards is now out, though the cause is still being investigated, firefighters say.
I’d like to commend the firefighters for their efforts, particularly those from HastingsBohemia Road who were the first on the scene within five minutes and who did afantastic job containing the fire before support appliances arrived from across thecounty.
"Crews also rescued a person who was still within the building, who had to betaken to hospital to be treated for smoke inhalation.
“All of the crews also did an excellent job to prevent the fire from spreading any moreextensively.”
Firefighters say they are on the scene of a major fire in St Leonards.
Crews were alerted at 10.45am to a blaze in the Hastings Hire Centre on Menzies Road.