TWO witnesses yesterday offered conflicting testimonies of the state of mind of the Nanyang Technological University (NTU) undergraduate who allegedly attacked his professor and then fell to his death in March.

One said that Mr David Hartanto Widjaja 'looked normal', while the other painted a picture of a troubled young man.

The pair of fellow NTU students who testified were Mr Nolang Fanani and Mr Edwin Lesmana Tjiong, close friends of Mr Widjaja from Indonesia.

They said they were not as close with him on campus here, but still kept in touch largely through online messenger platform MSN.

Mr Fanani, who saw Mr Widjaja only minutes before he allegedly stabbed Associate Professor Chan Kap Luk, said his friend 'looked normal' as he walked about 200m ahead of him towards the School of Electrical & Electronic Engineering. Mr Widjaja appeared unhurried and had his backpack slung casually over his shoulder, he said.

But Mr Tjiong, who goes to the same Queenstown church as Mr Widjaja, said his friend's infrequent attendance - after having been a regular - had raised alarm bells among church members.

Mr Tjiong said he and two other church members went to Mr Widjaja's hostel room the week before his death to offer him 'help and support', but he was not in at the time. He later promised them they could visit the following week.

Mr Tjiong also said that when he asked Mr Widjaja about how his final-year project was coming along, he got the reply that it was 'bad and troublesome'. However, Mr Widjaja said nothing more about the project, Prof Chan, or that his scholarship had been terminated.

Mr Fanani and Mr Tjiong are among the nine people whose names the Widjaja family submitted to the court as witnesses, on top of the current 28.

Forensic scientist Lim Chin Chin, who resumed her testimony on what happened in Prof Chan's office, said it was 'very likely' the student had stabbed the don.

Read the full story in Friday's edition of The Straits Times.