"It is only coincidental that this morning's arrest was made as Brown's family prepared to lay him to rest today," Faa Vaaelua said today.
"Today's arrest is pleasing and a great relief to achieve this result.
"This has come about through some tireless work by the police team working on the case and assisted by information provided from the public, including anonymous reports via Crimestoppers."
Arthur Brown's cousin, Geoff Brown, earlier told the Herald the unborn child was "holding a lot of people together" while they mourned a man described as "loving and generous" and "very caring and family oriented".
Brown said Arthur's death had hit the family hard and they were all finding strength in different ways.
"It is something you don't prepare for really," he said.
"It has hit us hard, all of us - we have family in Australia, America and Samoa - and this has affected not just us but our churches and our communities. Everyone is hurting."
Brown said on the night of Arthur's death he went to meet a friend for a catch up.
"I truly believe he was in the wrong place at the wrong time," he said.