SINGAPORE - A forensic pathologist who performed an autopsy on Madam Low Foong Meng, whose charred body was found inside her husband's law firm in the Afro Asia Building four years ago, found three cuts on her body which were likely to have been caused by a knife or a cleaver.

She also had five fractures to her skull, and the damage to her brain possibly rendered her unconscious, said Associate Professor Dr Gilbert Lau.

The senior consultant forensic pathologist with the Health Sciences Authority found the cause of Madam Low's death to be from the inhalation of fire fumes and extensive severe burns.

Prof Lau took to the witness stand on the second day of a murder trial in the High Court on Wednesday morning.

Govindasamy Nallaiah, 70, a former client of Madam Low's husband, Rengarajoo Rengasamy Balasamy stands accused of her murder.

The prosecution's case is that Govindasamy, angered over a legal fee dispute, took out a bicycle chain and padlock from his haversack and hit Madam Low, 56, on the head several times until she collapsed at her husband's firm on 10 Aug, 2011.

He then allegedly used a lighter to set some files on a table in the office on fire, and watched it spread, before leaving Madam Low unconscious inside the burning unit.

Prof Lau told the court that two of the threecuts he found on Madam Low were "defensive injuries". One almost sliced off the tip of her left middle finger, while another was a cut on her elbow.

The wounds were caused by "a sharp, cutting instrument", such as a knife or a cleaver, he said.

Madam Low's head injuries, meanwhile, caused some bleeding in the brain, but would not have been serious enough to cause her death, Prof Lau testified.

The presence of "copious amounts of soot" in her airways and lungs, and a "lethal" level of carbon monoxide in her blood, also meant that she must have been alive at the time of the fire, he added.

Prof Lau will be crossed-examined by Govindasamy's lawyers at a later date.

Security officer Mohamed Amin Arshad also took the stand on Wednesday morning, and testified that he saw Govindasamy entering the building that day.

Deliveryman Marco Jap is expected to take the stand on Wednesday afternoon. He supposedly saw Govindasamy holding on to a bicycle chain with a padlock in the office, and later heard loud "thud" sounds and a female voice screaming inside, before noticing smoke coming out of the office. Mr Jap then went to alert a security officer.

The trial continues.