"They were here, they were Australian citizens and they went back three or four years back to look after their mother," Fahim Mawjood told SBS.
"It is really shocking to know that you are no longer here with us," one relative admitted after learning the devastating news.
"You lost your lives on a holy day in a holy place. The sweet memories of Alex and yourself will live in our hearts forever."
The coordinated bomb blasts, which left almost 290 dead and 500 more wounded, ripped through luxury hotels, prominent churches and tourist landmarks in the capital Colombo and surrounding areas yesterday.
Authorities have not made public details on those held after Sunday's attacks. But a police source told AFP the 13 were detained at two locations in and around Colombo.
Prime Minister Scott Morrison echoed this sentiment and confirmed the Government would work with organisations on the ground to secure the safety of Australians in the island nation.
BREAKING: Australian mother and daughter amongst dead in Sri Lanka terror attacks
Devastating news just in.
- by
Katherine Davison
News has just emerged that an Australian woman and her 10-year-old daughter are among the 290 people killed in Easter Sunday's deadly terror attacks in Sri Lanka.
The website has confirmed that Manik Suriaaratchi and her daughter, Alexandria were in the church in Negombo when one of the bombs detonated.
The publication also claims that Manik's husband was in the car park at the time of the blast and was uninjured.
Here's what we know about the deadly terror attacks in Sri Lanka: